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cmake-policies (7)

Name

cmake-policies - CMake Policies Reference

Synopsis

Please see following description for synopsis

Description

CMAKE-POLICIES(7)                    CMake                   CMAKE-POLICIES(7)



NAME
       cmake-policies - CMake Policies Reference

INTRODUCTION
       Policies  in  CMake  are  used to preserve backward compatible behavior
       across multiple releases.  When a new policy is introduced, newer CMake
       versions will begin to warn about the backward compatible behavior.  It
       is possible to disable the warning by explicitly requesting the OLD, or
       backward  compatible  behavior using the cmake_policy() command.  It is
       also possible to request NEW, or non-backward compatible behavior for a
       policy,  also  avoiding  the  warning.   Each policy can also be set to
       either NEW or OLD behavior explicitly on  the  command  line  with  the
       CMAKE_POLICY_DEFAULT_CMP<NNNN> variable.

       A  policy is a deprecation mechanism and not a reliable feature toggle.
       A policy should almost never be set to OLD, except to silence  warnings
       in  an otherwise frozen or stable codebase, or temporarily as part of a
       larger migration path. The OLD behavior of each policy  is  undesirable
       and will be replaced with an error condition in a future release.

       The  cmake_minimum_required() command does more than report an error if
       a too-old version of CMake is used to build a project.   It  also  sets
       all  policies introduced in that CMake version or earlier to NEW behav-
       ior.  To manage policies without increasing the minimum required  CMake
       version, the if(POLICY) command may be used:

          if(POLICY CMP0990)
            cmake_policy(SET CMP0990 NEW)
          endif()

       This has the effect of using the NEW behavior with newer CMake releases
       which users may be using and not issuing a compatibility warning.

       The setting of a policy is confined in some cases to not  propagate  to
       the parent scope.  For example, if the files read by the include() com-
       mand or the find_package() command contain  a  use  of  cmake_policy(),
       that  policy  setting will not affect the caller by default.  Both com-
       mands accept an optional NO_POLICY_SCOPE keyword to control this behav-
       ior.

       The  CMAKE_MINIMUM_REQUIRED_VERSION variable may also be used to deter-
       mine whether to report an error on use of deprecated  macros  or  func-
       tions.

POLICIES INTRODUCED BY CMAKE 3.21
   CMP0126
       New in version 3.21.


       The set(CACHE) does not remove a normal variable of the same name.

       Starting  with  CMake 3.21, the set(CACHE) does not remove, in the cur-
       rent scope, any normal variable with the same name.

       The OLD behavior for this policy is  to  have  the  set(CACHE)  command
       removing the normal variable of the same name, if any. The NEW behavior
       for this policy is to keep the normal variable of the same name.

       This policy was introduced in CMake version 3.21.  Use  the  cmake_pol-
       icy()  command  to  set it to OLD or NEW explicitly.  Unlike many poli-
       cies, CMake version 3.21.0 does not warn when the policy is not set and
       simply  uses OLD behavior.  See documentation of the CMAKE_POLICY_WARN-
       ING_CMP0126 variable to control the warning.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0125
       New in version 3.21.


       The  find_file(),  find_path(),  find_library() and find_program() com-
       mands handle cache variables in the same way regardless of whether they
       are  defined  on the command line, with or without a type, or using the
       set() command.

       Starting with CMake 3.21, the find_file(), find_path(), find_library(),
       and  find_program()  commands  ensure  that the cache variables will be
       used in the same way regardless how they were defined  and  the  result
       will be always successful if the searched artifact exists.

       The  OLD  behavior for this policy is to have the find commands' behav-
       iors differ depending on how the cache variable  is  defined.  The  NEW
       behavior for this policy is to have consistent behavior.

       This  policy  was  introduced in CMake version 3.21. Use the cmake_pol-
       icy() command to set it to OLD or NEW explicitly.   Unlike  many  poli-
       cies, CMake version 3.21.0 does not warn when the policy is not set and
       simply uses OLD behavior.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0124
       New in version 3.21.


       The  loop  variables  created by foreach() command have now their scope
       restricted to the loop scope.

       Starting with CMake 3.21, the foreach() command ensures that  the  loop
       variables have their scope restricted to the loop scope.

       The  OLD behavior for this policy let the loop variables to exist, with
       an empty value, in the outer scope of loop scope.

       This policy was introduced in CMake version 3.21.  Use  the  cmake_pol-
       icy()  command  to  set it to OLD or NEW explicitly.  Unlike many poli-
       cies, CMake version 3.21.0 does not warn when the policy is not set and
       simply uses OLD behavior.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0123
       New in version 3.21.


       ARMClang cpu/arch compile and link flags must be set explicitly.

       CMake 3.20 and  lower  automatically  maps  the  CMAKE_SYSTEM_PROCESSOR
       variable  and  an  undocumented  CMAKE_SYSTEM_ARCH  to compile and link
       options for ARMClang.  For example, the -mcpu=cortex-m33 flag is  added
       when CMAKE_SYSTEM_PROCESSOR equals cortex-m33.  CMake requires projects
       to set either variable or  it  raises  a  fatal  error.   However,  the
       project  may  need  to  additionally  specify  CPU  features using e.g.
       -mcpu=cortex-m33+nodsp, conflicting with the -mcpu=cortex-m33 added  by
       CMake.  This results in either link errors or unusable binaries.

       CMake 3.21 and above prefer instead to not add any cpu/arch compile and
       link flags automatically.  Instead, projects must specify them  explic-
       itly.   This  policy  provides compatibility for projects that have not
       been updated.

       The OLD behavior of this policy requires projects that use ARMClang  to
       set either CMAKE_SYSTEM_PROCESSOR or CMAKE_SYSTEM_ARCH and it automati-
       cally adds a compile option -mcpu= or -march= and a link option  --cpu=
       based  on  those  variables.   The NEW behavior does not add compile or
       link options, and projects are responsible for setting correct options.

       This policy was introduced in CMake version 3.21.  CMake version 3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0122
       New in version 3.21.


       UseSWIG use library name conventions for CSharp language.

       Starting with CMake 3.21, UseSWIG generates now a library using default
       naming conventions. This policy provides  compatibility  with  projects
       that expect the legacy behavior.

       This policy was introduced in CMake version 3.21.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0121
       New in version 3.21.


       The list() command now detects invalid indices.

       Prior to CMake version 3.21, the list() command's GET, INSERT, SUBLIST,
       and REMOVE_AT subcommands did not detect invalid index arguments.

       The OLD behavior of this policy is for invalid indices to be treated as
       their integer value (if any) at the start of the string.  For  example,
       2good4you  is  a  2  and not_an_integer is a 0. The NEW behavior is for
       invalid indices to trigger an error.

       This policy was introduced in CMake version 3.21.  CMake version 3.21.0
       warns  when  the  policy  is  not  set  and  uses OLD behavior. Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.20
   CMP0120
       New in version 3.20.


       The WriteCompilerDetectionHeader module is removed.

       CMake  versions  3.1 through 3.19 provide this module to generate a C++
       compatibility layer by re-using information from CMake's table of  pre-
       processor checks for cmake-compile-features(7).  However:

       o Those  granular  features  have  been superseded by meta-features for
         Requiring Language Standards such as cxx_std_11.   Therefore  no  new
         granular  feature  checks will be added and projects will need to use
         other means to conditionally use new C++ features.

       o The module exposes some of CMake's implementation details directly to
         C++ translation units.

       o The  module's approach effectively provides a header file with CMake,
         thus tying the version of the header to the version of  CMake.   Many
         projects found that the WriteCompilerDetectionHeader was best used by
         manually generating its header locally with a recent version of CMake
         and then bundling it with the project source so that it could be used
         with older CMake versions.

       For reasons including the above, CMake 3.20 and  above  prefer  to  not
       provide  the WriteCompilerDetectionHeader module.  This policy provides
       compatibility for projects that have not  been  ported  away  from  it.
       Projects using the module should be updated to stop using it.  Alterna-
       tives include:

       o Bundle a copy of the generated header in the project's source.

       o Use a third-party alternative, such as the CC0-licensed Hedley.

       o Drop support for compilers too old to provide the features natively.

       The OLD behavior of this policy is  for  inclusion  of  the  deprecated
       WriteCompilerDetectionHeader  module  to work.  The NEW behavior is for
       inclusion of the module to fail as if it does not exist.

       This policy was introduced in CMake version 3.20.  CMake version 3.21.0
       warns  when  the  policy  is  not  set  and  uses OLD behavior. Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0119
       New in version 3.20.


       LANGUAGE  source  file  property  explicitly compiles as specified lan-
       guage.

       The LANGUAGE source file property is documented to mean that the source
       file  is  written  in the specified language.  In CMake 3.19 and below,
       setting this property causes CMake to compile the source file using the
       compiler  for  the  specified  language.   However,  it  only passes an
       explicit flag to tell the compiler to treat the source as the specified
       language  for MSVC-like, XL, and Embarcadero compilers for the CXX lan-
       guage.  CMake 3.20 and above prefer to also explicitly  tell  the  com-
       piler  to  use  the specified language using a flag such as -x c on all
       compilers for which such flags are known.

       This policy provides compatibility for  projects  that  have  not  been
       updated  to expect this behavior.  For example, some projects were set-
       ting the LANGUAGE property to C on assembly-language .S source files in
       order  to  compile  them using the C compiler.  Such projects should be
       updated to use enable_language(ASM), for which CMake will often  choose
       the C compiler as the assembler on relevant platforms anyway.

       The  OLD  behavior  for this policy is to interpret the LANGUAGE <LANG>
       property using its undocumented meaning to "use the  <LANG>  compiler".
       The  NEW  behavior  for this policy is to interpret the LANGUAGE <LANG>
       property using its documented meaning to "compile as a <LANG> source".

       This policy was introduced in CMake version 3.20.  Use  the  cmake_pol-
       icy()  command  to  set it to OLD or NEW explicitly.  Unlike many poli-
       cies, CMake version 3.21.0 does not warn when this policy  is  not  set
       and simply uses OLD behavior.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0118
       New in version 3.20.


       The GENERATED source file property is now visible in all directories.

       Whether or not a source file is generated is an  all-or-nothing  global
       property  of  the source.  Consequently, the associated GENERATED prop-
       erty is now visible from any directory scope, not only from  the  scope
       for which it was set.

       Additionally,  the  GENERATED  property  may now be set only to boolean
       values, and may not be turned off once turned on.

       The OLD behavior of this policy is to only allow GENERATED to be  visi-
       ble from the directory scope for which it was set.  The NEW behavior on
       the other hand allows it to be visible from any scope.

       This policy was introduced in CMake version 3.20.  Use  the  cmake_pol-
       icy()  command  to  set it to OLD or NEW explicitly.  Unlike many poli-
       cies, CMake version 3.21.0 does not warn when this policy  is  not  set
       and simply uses OLD behavior with regard to visibility of the GENERATED
       property.  However, CMake does warn about setting the  GENERATED  prop-
       erty to a non-boolean value.

   CMP0117
       New in version 3.20.


       MSVC RTTI flag /GR is not added to CMAKE_CXX_FLAGS by default.

       When  using  MSVC-like compilers in CMake 3.19 and below, the RTTI flag
       /GR is added to CMAKE_CXX_FLAGS by default.  This behavior is left from
       support  for  MSVC  versions from Visual Studio 2003 and below that did
       not enable RTTI by default.  It is no longer  necessary.   Furthermore,
       it is problematic for projects that want to change to /GR- programmati-
       cally.   In   particular,   it   requires   string   editing   of   the
       CMAKE_CXX_FLAGS variable with knowledge of the CMake builtin default so
       it can be replaced.

       CMake 3.20 and above  prefer  to  leave  out  /GR  from  the  value  of
       CMAKE_CXX_FLAGS by default.

       This  policy  provides  compatibility  with projects that have not been
       updated to expect the lack of the /GR flag.  The policy  setting  takes
       effect as of the first project() or enable_language() command that ini-
       tializes CMAKE_CXX_FLAGS.

       NOTE:
          Once the policy has taken effect at the top of a project for a given
          language, that choice must be used throughout the tree for that lan-
          guage.  In projects that have nested projects in subdirectories,  be
          sure to convert everything together.

       The  OLD  behavior for this policy is to place the MSVC /GR flag in the
       default CMAKE_CXX_FLAGS cache entry.  The NEW behavior for this  policy
       is to not place the MSVC /GR flag in the default cache entry.

       This  policy  was introduced in CMake version 3.20.  Use the cmake_pol-
       icy() command to set it to OLD or NEW explicitly.   Unlike  many  poli-
       cies,  CMake  version  3.21.0 does not warn when this policy is not set
       and simply uses OLD behavior.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0116
       New in version 3.20.


       Ninja generators transform DEPFILE s from add_custom_command().

       In  CMake  3.19  and  below,  files  given  to  the DEPFILE argument of
       add_custom_command() were passed directly to Ninja's  depfile  variable
       without  any  path  resolution. This meant that if add_custom_command()
       was called from a subdirectory  (created  by  add_subdirectory()),  the
       DEPFILE  argument  would  have  to be either an absolute path or a path
       relative to CMAKE_BINARY_DIR, rather than CMAKE_CURRENT_BINARY_DIR.  In
       addition,  no  transformation  was  done on the file listed in DEPFILE,
       which meant that the paths within the DEPFILE  had  the  same  restric-
       tions.

       Starting   with  CMake  3.20,  the  DEPFILE  argument  is  relative  to
       CMAKE_CURRENT_BINARY_DIR (unless it is absolute), and the paths in  the
       DEPFILE are also relative to CMAKE_CURRENT_BINARY_DIR.  CMake automati-
       cally transforms the paths in the DEPFILE (unless  they  are  absolute)
       after the custom command is run. The file listed in DEPFILE is not mod-
       ified in any way. Instead, CMake writes the transformation to  its  own
       internal  file,  and passes this internal file to Ninja's depfile vari-
       able.  This transformation happens regardless of whether or not DEPFILE
       is  relative,  and regardless of whether or not add_custom_command() is
       called from a subdirectory.

       The OLD behavior for this policy is to pass the DEPFILE to Ninja  unal-
       tered.  The  NEW  behavior  for this policy is to transform the DEPFILE
       after running the custom command. The status of CMP0116 is recorded  at
       the time of the custom command's creation, and you can have custom com-
       mands in the same directory with different values for CMP0116  by  set-
       ting the policy before each custom command.

       This  policy  was  introduced in CMake version 3.20.  Unlike most poli-
       cies, CMake version 3.21.0 does not warn by default when this policy is
       not  set (unless DEPFILE is used in a subdirectory) and simply uses OLD
       behavior.  See documentation of the CMAKE_POLICY_WARNING_CMP0116  vari-
       able to control the warning.

   CMP0115
       New in version 3.20.


       Source file extensions must be explicit.

       In  CMake  3.19  and  below, if a source file could not be found by the
       name specified, it would append a list of known extensions to the  name
       to see if the file with the extension could be found. For example, this
       would allow the user to run:

          add_executable(exe main)

       and put main.c in the executable without specifying the extension.

       Starting in CMake 3.20, CMake prefers all source files  to  have  their
       extensions explicitly listed:

          add_executable(exe main.c)

       The  OLD  behavior for this policy is to implicitly append known exten-
       sions to source files if they can't be found. The NEW behavior of  this
       policy  is  to  not  append  known  extensions  and  require them to be
       explicit.

       This policy was introduced in CMake version 3.20.  CMake version 3.21.0
       warns  when  the  policy  is  not  set  and  uses OLD behavior. Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.19
   CMP0114
       New in version 3.19.


       ExternalProject step targets fully adopt their steps.

       The  ExternalProject_Add()  STEP_TARGETS  option,  and the ExternalPro-
       ject_Add_StepTargets() function, can be used to  create  build  targets
       for individual steps of an external project.

       In CMake 3.18 and below, step targets have some limitations:

       o Step  targets  always  depend  on  targets  named by the ExternalPro-
         ject_Add() DEPENDS option even though not all steps  need  them.   In
         order to allow step targets to be created without those dependencies,
         the  ExternalProject_Add()  INDEPENDENT_STEP_TARGETS  option  or  the
         ExternalProject_Add_StepTargets()  NO_DEPENDS  option  may  be  used.
         However, adding such "independent" step targets makes sense only  for
         specific  steps  such  as download, update, and patch because they do
         not need any of the external project's build dependencies.   Further-
         more,  it  does not make sense to create independent step targets for
         steps that depend on  non-independent  steps.   Such  rules  are  not
         enforced,  and  projects  that  do not follow them can generate build
         systems with confusing and generator-specific behavior.

       o Step targets hold copies of the custom  commands  implementing  their
         steps that are separate from the copies in the primary target created
         by ExternalProject_Add(), and the primary target does not  depend  on
         the  step  targets.  In parallel builds that drive the primary target
         and step targets concurrently, multiple copies of the steps' commands
         may run concurrently and race each other.

         Also, prior to policy CMP0113, the step targets generated by Makefile
         Generators also contain all the custom commands on which  their  step
         depends.   This can lead to repeated execution of those steps even in
         serial builds.

       In CMake 3.19 and above, the ExternalProject module prefers  a  revised
       design to address these problems:

       o Each  step  is  classified  as "independent" if it does not depend on
         other targets named by the ExternalProject_Add() DEPENDS.  The prede-
         fined steps are automatically classified by default:

         o The download, update, and patch steps are independent.

         o The configure, build, test, and install steps are not.

         For  custom steps, the ExternalProject_Add_Step() command provides an
         INDEPENDENT option to mark them as independent.  It is  an  error  to
         mark a step as independent if it depends on other steps that are not.
         Note that this use of the term "independent" refers only to  indepen-
         dence  from  external targets and is orthogonal to a step's dependen-
         cies on other steps.

       o Step targets created by the ExternalProject_Add() STEP_TARGETS option
         or the ExternalProject_Add_Step() function are now independent if and
         only if their steps are  marked  as  independent.   The  ExternalPro-
         ject_Add()    INDEPENDENT_STEP_TARGETS    option   and   ExternalPro-
         ject_Add_StepTargets() NO_DEPENDS option are no longer allowed.

       o Step targets, when created, are fully  responsible  for  holding  the
         custom commands implementing their steps.  The primary target created
         by ExternalProject_Add() depends on the step targets,  and  the  step
         targets  depend  on  each other.  The target-level dependencies match
         the file-level dependencies used by  the  custom  commands  for  each
         step.

         When     the     ExternalProject_Add()     UPDATE_DISCONNECTED     or
         TEST_EXCLUDE_FROM_MAIN  option   is   used,   or   the   ExternalPro-
         ject_Add_Step()  EXCLUDE_FROM_MAIN  option is used for a custom step,
         some step targets may be created automatically.  These are needed  to
         hold  the  steps commonly depended upon by the primary target and the
         disconnected step targets.

       Policy CMP0114 provides compatibility for projects that have  not  been
       updated  to  expect the new behavior.  The OLD behavior for this policy
       is to use the above-documented behavior from 3.18 and below.   The  NEW
       behavior  for  this policy is to use the above-documented behavior pre-
       ferred by 3.19 and above.

       This policy was introduced in CMake version 3.19.  CMake version 3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

   CMP0113
       New in version 3.19.


       Makefile Generators do not repeat custom commands from target dependen-
       cies.

       Consider a chain of custom commands split across two dependent targets:

          add_custom_command(OUTPUT output-not-created
            COMMAND ... DEPENDS ...)
          set_property(SOURCE output-not-created PROPERTY SYMBOLIC 1)
          add_custom_command(OUTPUT output-created
            COMMAND ... DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/output-not-created)
          add_custom_target(first DEPENDS output-not-created)
          add_custom_target(second DEPENDS output-created)
          add_dependencies(second first)

       In  CMake  3.18  and  lower, the Makefile generators put a copy of both
       custom commands in the Makefile  for  target  second  even  though  its
       dependency  on  target first ensures that the first custom command runs
       before the second.  Running make second would cause  the  first  custom
       command  to  run  once in the first target and then again in the second
       target.

       CMake 3.19 and above prefer to not duplicate custom commands in a  tar-
       get  that  are  already  generated in other targets on which the target
       depends (directly or indirectly).  This policy  provides  compatibility
       for projects that have not been updated to expect the new behavior.  In
       particular, projects that relied on the duplicate execution or that did
       not properly set the SYMBOLIC source file property may be affected.

       The  OLD  behavior  for  this policy is to duplicate custom commands in
       dependent targets.  The NEW behavior of this policy is to not duplicate
       custom commands in dependent targets.

       This  policy  was  introduced in CMake version 3.19.  Unlike many poli-
       cies, CMake version 3.21.0 does not warn when this policy  is  not  set
       and simply uses OLD behavior.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0112
       New in version 3.19.


       Target file component generator expressions do not add target dependen-
       cies.

       The  following target-based generator expressions that query for direc-
       tory or file name components no longer add a dependency on  the  evalu-
       ated target.

          o TARGET_FILE_NAME

          o TARGET_FILE_DIR

          o TARGET_LINKER_FILE_BASE_NAME

          o TARGET_LINKER_FILE_NAME

          o TARGET_LINKER_FILE_DIR

          o TARGET_SONAME_FILE_NAME

          o TARGET_SONAME_FILE_DIR

          o TARGET_PDB_FILE_NAME

          o TARGET_PDB_FILE_DIR

          o TARGET_BUNDLE_DIR

          o TARGET_BUNDLE_CONTENT_DIR

       In  CMake  3.18  and  lower a dependency on the evaluated target of the
       above generator expressions would always  be  added.   CMake  3.19  and
       above prefer to not add this dependency.  This policy provides compati-
       bility for projects that have not been updated to expect the new behav-
       ior.

       The  OLD  behavior for this policy is to add a dependency on the evalu-
       ated target for the above generator expressions.  The NEW  behavior  of
       this  policy is to not add a dependency on the evaluated target for the
       above generator expressions.

       This policy was introduced in CMake version 3.19.   Unlike  many  poli-
       cies, CMake version 3.21.0 does not warn by default when this policy is
       not set and  simply  uses  OLD  behavior.   See  documentation  of  the
       CMAKE_POLICY_WARNING_CMP0112 variable to control the warning.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0111
       New in version 3.19.


       An imported target missing its location property fails  during  genera-
       tion.

       Imported  Targets  for library files and executables require that their
       location  on  disk  is  specified  in  a  target   property   such   as
       IMPORTED_LOCATION,  IMPORTED_IMPLIB, or a per-configuration equivalent.
       If a needed location property is not set, CMake 3.18 and below generate
       the  string <TARGET_NAME>-NOTFOUND in its place, which results in fail-
       ures of the corresponding rules at build time.  CMake  3.19  and  above
       prefer  instead  to raise an error during generation.  This policy pro-
       vides compatibility for projects that have not been updated  to  expect
       the new behavior.

       The  OLD  behavior  of  this  policy  is to generate the location of an
       imported unknown, static or shared library target as <TARGET_NAME>-NOT-
       FOUND if not set.  The NEW behavior is to raise an error.

       This policy was introduced in CMake version 3.19.  CMake version 3.21.0
       warns when the policy is  not  set  and  uses  OLD  behavior.  Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0110
       New in version 3.19.


       add_test() supports arbitrary characters in test names.

       add_test() can now (officially) create tests with whitespace and  other
       special characters in its name.  Before CMake version 3.19 that was not
       allowed, however, it was possible to work  around  this  limitation  by
       explicitly  putting  escaped  quotes  around  the  test's  name  in the
       add_test command.

       Although never officially supported several projects in the wild  found
       and  implemented  this workaround.  However, the new change which offi-
       cially allows the add_test command to support whitespace and other spe-
       cial characters in test names now breaks that workaround.  In order for
       these projects to work smoothly with newer CMake versions, this  policy
       was introduced.

       The  OLD behavior of this policy is to still prevent add_test from han-
       dling whitespace and special characters properly (if not using the men-
       tioned  workaround).   The  NEW behavior on the other hand allows names
       with whitespace and special characters for tests created by add_test.

       This policy was introduced in CMake version 3.19.  CMake version 3.21.0
       warns  when  the  policy  is  not  set  and  uses OLD behavior. Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

   CMP0109
       New in version 3.19.


       find_program() requires permission to execute but not to read.

       In CMake 3.18 and below, the find_program() command on UNIX would  find
       files that are readable without requiring execute permission, and would
       not find files that are executable without read permission.   In  CMake
       3.19  and above, find_program now prefers to require execute permission
       but not read  permission.   This  policy  provides  compatibility  with
       projects that have not been updated to expect the new behavior.

       The  OLD  behavior  for this policy is for find_program to require read
       permission but not execute permission.  The NEW behavior for this  pol-
       icy is for find_program to require execute permission but not read per-
       mission.

       This policy was introduced in CMake version 3.19.  CMake version 3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.18
   CMP0108
       New in version 3.18.


       A target is not allowed to link to itself even through an ALIAS target.

       In  CMake  3.17  and  below,  a  target can link to a target aliased to
       itself.

       The OLD behavior for this policy is to allow a target to link to a tar-
       get aliased to itself.

       The  NEW  behavior  of  this  policy  is to prevent a target to link to
       itself through an ALIAS target.

       This policy was introduced in CMake version 3.17.  Use  the  cmake_pol-
       icy()  command  to  set it to OLD or NEW explicitly.  Unlike many poli-
       cies, CMake version 3.21.0 does not warn when this policy  is  not  set
       and simply uses OLD behavior.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0107
       New in version 3.18.


       It is not allowed to create an ALIAS target with the same  name  as  an
       another target.

       In  CMake  3.17  and  below,  an ALIAS target can overwrite silently an
       existing target with the same name.

       The OLD behavior for this policy is to allow target overwrite.

       The NEW behavior of this policy is to prevent target overwriting.

       This policy was introduced in CMake version 3.17.  Use  the  cmake_pol-
       icy()  command  to  set it to OLD or NEW explicitly.  Unlike many poli-
       cies, CMake version 3.21.0 does not warn when this policy  is  not  set
       and simply uses OLD behavior.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0106
       New in version 3.18.


       The Documentation module is removed.

       The Documentation was added as a support mechanism for the VTK  project
       and  was tuned for that project. Instead of CMake providing this module
       with (now old) VTK patterns for cache variables and required  packages,
       the module is now deprecated by CMake itself.

       The OLD behavior of this policy is for Documentation to add cache vari-
       ables and find VTK documentation dependent packages. The  NEW  behavior
       is to act as an empty module.

       This policy was introduced in CMake version 3.18.  CMake version 3.21.0
       warns when the policy is  not  set  and  uses  OLD  behavior.  Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0105
       New in version 3.18.


       LINK_OPTIONS and INTERFACE_LINK_OPTIONS target properties are now  used
       for the device link step.

       In  CMake  3.17 and below, link options are not used by the device link
       step.

       The OLD behavior for this policy is to ignore the link options.

       The NEW behavior of this policy is to use the link options  during  the
       device link step.

       This  policy  was introduced in CMake version 3.17.  Use the cmake_pol-
       icy() command to set it to OLD or NEW explicitly.   Unlike  many  poli-
       cies,  CMake  version  3.21.0 does not warn when this policy is not set
       and simply uses OLD behavior.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0104
       New in version 3.18.


       Initialize   CMAKE_CUDA_ARCHITECTURES  when  CMAKE_CUDA_COMPILER_ID  is
       NVIDIA.  Raise an error if CUDA_ARCHITECTURES is empty.

       CMAKE_CUDA_ARCHITECTURES introduced in CMake 3.18 is used to initialize
       CUDA_ARCHITECTURES,  which  passes correct code generation flags to the
       CUDA compiler.

       Previous to this users had to  manually  specify  the  code  generation
       flags.  This policy is for backwards compatibility with manually speci-
       fying code generation flags.

       The OLD behavior for this policy is to not initialize CMAKE_CUDA_ARCHI-
       TECTURES  when  CMAKE_CUDA_COMPILER_ID is NVIDIA.  Empty CUDA_ARCHITEC-
       TURES is allowed.

       The NEW behavior of this policy is to  initialize  CMAKE_CUDA_ARCHITEC-
       TURES  when  CMAKE_CUDA_COMPILER_ID  is  NVIDIA  and  raise an error if
       CUDA_ARCHITECTURES is empty during generation.

       If CUDA_ARCHITECTURES is set to a false value  no  architectures  flags
       are  passed  to the compiler. This is intended to support packagers and
       the rare cases where full control over the passed flags is required.

       This policy was introduced in CMake version 3.18.  CMake version 3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   Examples
          set_target_properties(tgt PROPERTIES CUDA_ARCHITECTURES "35;50;72")

       Generates code for real and virtual architectures 30, 50 and 72.

          set_property(TARGET tgt PROPERTY CUDA_ARCHITECTURES 70-real 72-virtual)

       Generates code for real architecture 70 and virtual architecture 72.

          set_property(TARGET tgt PROPERTY CUDA_ARCHITECTURES OFF)

       CMake will not pass any architecture flags to the compiler.

   CMP0103
       New in version 3.18.


       Multiple  calls to export() command with same FILE without APPEND is no
       longer allowed.

       In CMake 3.17 and below, multiple calls to export()  command  with  the
       same FILE without APPEND are accepted silently but only the last occur-
       rence is taken into account during the generation.

       The OLD behavior for this policy is to ignore the multiple  occurrences
       of
              export() command except the last one.

       The  NEW behavior of this policy is to raise an error on second call to
       export() command with same FILE without APPEND.

       This policy was introduced in CMake version 3.18.  CMake version 3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.17
   CMP0102
       New in version 3.17.


       The  mark_as_advanced()  command no longer creates a cache entry if one
       does not already exist.

       In CMake 3.16 and below, if a variable was not defined at all  or  just
       defined  locally,  the  mark_as_advanced()  command  would create a new
       cache entry with an UNINITIALIZED type and no value. When a find_path()
       (or  other  similar  find_  command) would next run, it would find this
       undefined cache entry and set it up with an empty  string  value.  This
       process would end up deleting the local variable in the process (due to
       the way the cache works), effectively clearing any stored find_ results
       that were only available in the local scope.

       The  OLD  behavior for this policy is to create the empty cache defini-
       tion.  The NEW behavior of this policy is to ignore variables which  do
       not already exist in the cache.

       This  policy  was introduced in CMake version 3.17.  Use the cmake_pol-
       icy() command to set it to OLD or NEW explicitly.   Unlike  many  poli-
       cies,  CMake  version  3.21.0 does not warn when this policy is not set
       and simply uses OLD behavior.   See  documentation  of  the  CMAKE_POL-
       ICY_WARNING_CMP0102 variable to control the warning.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0101
       New in version 3.17.


       target_compile_options() now honors BEFORE keyword in all scopes.

       In CMake 3.16 and below the target_compile_options() ignores the BEFORE
       keyword in private scope. CMake 3.17 and later honors BEFORE keyword in
       all scopes. This policy provides compatibility for projects  that  have
       not been updated to expect the new behavior.

       The OLD behavior for this policy is to not honor BEFORE keyword in pri-
       vate scope. The NEW behavior of this policy is to honor BEFORE  keyword
       in all scopes.

       This  policy  was introduced in CMake version 3.17.  Use the cmake_pol-
       icy() command to set it to OLD or NEW explicitly.   Unlike  many  poli-
       cies,  CMake  version  3.21.0 does not warn when this policy is not set
       and simply uses OLD behavior.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0100
       New in version 3.17.


       Let AUTOMOC and AUTOUIC process header files that end with a .hh exten-
       sion.

       Since version 3.17, CMake processes header files that end  with  a  .hh
       extension  in  AUTOMOC  and  AUTOUIC.  In earlier CMake versions, these
       header files were ignored by AUTOMOC and AUTOUIC.

       This policy affects how header files that end with a .hh extension  get
       treated in AUTOMOC and AUTOUIC.

       The OLD behavior for this policy is to ignore .hh header files in AUTO-
       MOC and AUTOUIC.

       The NEW behavior for this policy is to  process  .hh  header  files  in
       AUTOMOC and AUTOUIC just like other header files.

       NOTE:
          To  silence  the  CMP0100  warning source files can be excluded from
          AUTOMOC and AUTOUIC processing by setting the source file properties
          SKIP_AUTOMOC, SKIP_AUTOUIC or SKIP_AUTOGEN.

              # Source skip example:
              set_property(SOURCE /path/to/file1.hh PROPERTY SKIP_AUTOMOC ON)
              set_property(SOURCE /path/to/file2.hh PROPERTY SKIP_AUTOUIC ON)
              set_property(SOURCE /path/to/file3.hh PROPERTY SKIP_AUTOGEN ON)

       This  policy  was  introduced  in  CMake version 3.17.0.  CMake version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0099
       New in version 3.17.


       Target link properties INTERFACE_LINK_OPTIONS,  INTERFACE_LINK_DIRECTO-
       RIES  and INTERFACE_LINK_DEPENDS are now transitive over private depen-
       dencies of static libraries.

       In CMake 3.16 and below  the  interface  link  properties  attached  to
       libraries  are  not  propagated  for  private  dependencies  of  static
       libraries.  Only the libraries themselves are propagated  to  link  the
       dependent  binary.  CMake 3.17 and later prefer to propagate all inter-
       face link properties.  This policy provides compatibility for  projects
       that have not been updated to expect the new behavior.

       The  OLD  behavior  for  this policy is to not propagate interface link
       properties. The NEW behavior of this policy is to  propagate  interface
       link properties.

       This  policy  was introduced in CMake version 3.17.  Use the cmake_pol-
       icy() command to set it to OLD or NEW explicitly.   Unlike  many  poli-
       cies,  CMake  version  3.21.0 does not warn when this policy is not set
       and simply uses OLD behavior.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0098
       New in version 3.17.


       FindFLEX  runs  flex in directory CMAKE_CURRENT_BINARY_DIR when execut-
       ing.

       The module provides a FLEX_TARGET macro which  generates  FLEX  output.
       In  CMake 3.16 and below the macro would generate a custom command that
       runs flex in the current source directory.  CMake 3.17 and later prefer
       to  run  it  in the build directory and use CMAKE_CURRENT_BINARY_DIR as
       the WORKING_DIRECTORY of  its  add_custom_command()  invocation.   This
       ensures  that  any implicitly generated file is written relative to the
       build tree rather than the source tree, unless the  generated  file  is
       provided as absolute path.

       This  policy  provides  compatibility  for  projects that have not been
       updated to expect the new behavior.

       The OLD behavior for this policy is for FLEX_TARGET to use the  current
       source  directory  for  the  WORKING_DIRECTORY  and  where  to generate
       implicit files. The NEW behavior of this policy is to use  the  current
       binary  directory  for the WORKING_DIRECTORY relative to which implicit
       files are generated unless provided as absolute path.

       This policy was introduced in CMake version 3.17.  Use  the  cmake_pol-
       icy()  command  to  set it to OLD or NEW explicitly.  Unlike many poli-
       cies, CMake version 3.21.0 does not warn when this policy  is  not  set
       and simply uses OLD behavior.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.16
   CMP0097
       New in version 3.16.


       ExternalProject_Add() with GIT_SUBMODULES "" initializes no submodules.

       The module provides a GIT_SUBMODULES option which controls what submod-
       ules  to  initialize  and  update. Starting with CMake 3.16, explicitly
       setting GIT_SUBMODULES to an empty string means no submodules  will  be
       initialized or updated.

       This  policy  provides  compatibility  for  projects that have not been
       updated to expect the new behavior.

       The OLD behavior for this policy is for GIT_SUBMODULES when set  to  an
       empty  string  to  initialize  and  update all git submodules.  The NEW
       behavior for this policy is for GIT_SUBMODULES when  set  to  an  empty
       string to initialize and update no git submodules.

       This  policy  was introduced in CMake version 3.16.  Use the cmake_pol-
       icy() command to set it to OLD or NEW explicitly.   Unlike  most  poli-
       cies,  CMake  version  3.21.0 does not warn when this policy is not set
       and simply uses OLD behavior.

   CMP0096
       New in version 3.16.


       The project() command preserves leading zeros in version components.

       When a VERSION <major>[.<minor>[.<patch>[.<tweak>]]]] argument is given
       to  the  project()  command,  it  stores  the  version  string  in  the
       PROJECT_VERSION variable and stores individual integer  version  compo-
       nents  in PROJECT_VERSION_{MAJOR,MINOR,PATCH,TWEAK} variables (see pol-
       icy CMP0048).  CMake 3.15 and below dropped  leading  zeros  from  each
       component.   CMake  3.16  and  higher prefer to preserve leading zeros.
       This policy provides compatibility for  projects  that  have  not  been
       updated to expect the new behavior.

       The  OLD behavior of this policy drops leading zeros in all components,
       e.g.  such that version 1.07.06 becomes 1.7.6.   The  NEW  behavior  of
       this  policy  preserves  the leading zeros in all components, such that
       version 1.07.06 remains unchanged.

       This policy was introduced in CMake version 3.16.   Unlike  many  poli-
       cies,  CMake  version  3.21.0 does not warn when this policy is not set
       and simply uses the OLD behavior.  Use the  cmake_policy()  command  to
       set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0095
       New in version 3.16.


       RPATH entries are properly escaped in the  intermediary  CMake  install
       script.

       In CMake 3.15 and earlier, RPATH entries set via CMAKE_INSTALL_RPATH or
       via INSTALL_RPATH have not been escaped before being inserted into  the
       cmake_install.cmake  script. Dynamic linkers on ELF-based systems (e.g.
       Linux and FreeBSD) allow certain keywords in  RPATH  entries,  such  as
       ${ORIGIN}  (More  details are available in the ld.so man pages on those
       systems). The syntax of these keywords can match CMake's variable  syn-
       tax.  In  order  to  not  be  substituted  (usually to an empty string)
       already by the intermediary cmake_install.cmake script, the user had to
       double-escape   such   RPATH  keywords,  e.g.   set(CMAKE_INSTALL_RPATH
       "\\\${ORIGIN}/../lib").  Since  the  intermediary   cmake_install.cmake
       script  is an implementation detail of CMake, CMake 3.16 and later will
       make sure RPATH entries are inserted literally by escaping any  coinci-
       dental CMake syntax.

       The  OLD  behavior of this policy is to not escape RPATH entries in the
       intermediary cmake_install.cmake script. The NEW behavior is  to  prop-
       erly  escape coincidental CMake syntax in RPATH entries when generating
       the intermediary cmake_install.cmake script.

       This policy was introduced in CMake version 3.16. CMake version  3.21.0
       warns  when the policy is not set and detected usage of CMake-like syn-
       tax and uses OLD behavior. Use the cmake_policy() command to set it  to
       OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.15
   CMP0094
       New in version 3.15.


       Modules FindPython3, FindPython2 and FindPython use LOCATION for lookup
       strategy.

       Starting  with  CMake  3.15, Modules FindPython3, FindPython2 and Find-
       Python   set    value    LOCATION    for,    respectively,    variables
       Python3_FIND_STRATEGY,  Python2_FIND_STRATEGY and Python_FIND_STRATEGY.
       This policy provides compatibility with projects that expect the legacy
       behavior.

       The  OLD  behavior  for  this  policy  set  value VERSION for variables
       Python3_FIND_STRATEGY, Python2_FIND_STRATEGY and Python_FIND_STRATEGY.

       This policy was introduced in CMake version 3.15.  Use  the  cmake_pol-
       icy()  command  to  set it to OLD or NEW explicitly.  Unlike many poli-
       cies, CMake version 3.21.0 does not warn when this policy  is  not  set
       and simply uses the OLD behavior.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0093
       New in version 3.15.


       FindBoost reports Boost_VERSION in x.y.z format.

       In CMake 3.14 and below the module would report the Boost version  num-
       ber  as  specified  in the preprocessor definition BOOST_VERSION in the
       boost/version.hpp file. In CMake 3.15 and later it  is  preferred  that
       the  reported  version  number matches the x.y.z format reported by the
       CMake package shipped with Boost 1.70.0 and later. The macro  value  is
       still reported in the Boost_VERSION_MACRO variable.

       The  OLD behavior for this policy is for FindBoost to report Boost_VER-
       SION as specified  in  the  preprocessor  definition  BOOST_VERSION  in
       boost/version.hpp. The NEW behavior for this policy is for FindBoost to
       report Boost_VERSION in x.y.z format.

       This policy was introduced in CMake version 3.15.  Use  the  cmake_pol-
       icy()  command  to  set it to OLD or NEW explicitly.  Unlike many poli-
       cies, CMake version 3.21.0 does not warn when this policy  is  not  set
       and simply uses the OLD behavior.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0092
       New in version 3.15.


       MSVC warning flags are not in CMAKE_<LANG>_FLAGS by default.

       When using MSVC-like compilers in CMake 3.14 and below,  warning  flags
       like  /W3 are added to CMAKE_<LANG>_FLAGS by default.  This is problem-
       atic for projects that want to choose a different  warning  level  pro-
       grammatically.   In  particular,  it  requires  string  editing  of the
       CMAKE_<LANG>_FLAGS  variables  with  knowledge  of  the  CMake  builtin
       defaults so they can be replaced.

       CMake  3.15  and above prefer to leave out warning flags from the value
       of CMAKE_<LANG>_FLAGS by default.

       This policy provides compatibility with projects  that  have  not  been
       updated  to expect the lack of warning flags.  The policy setting takes
       effect as of the first project() or enable_language() command that ini-
       tializes CMAKE_<LANG>_FLAGS for a given language <LANG>.

       NOTE:
          Once the policy has taken effect at the top of a project for a given
          language, that choice must be used throughout the tree for that lan-
          guage.   In projects that have nested projects in subdirectories, be
          sure to convert everything together.

       The OLD behavior for this policy is to place MSVC warning flags in  the
       default  CMAKE_<LANG>_FLAGS  cache  entries.  The NEW behavior for this
       policy is to not place MSVC warning flags in the default cache entries.

       This policy was introduced in CMake version 3.15.  Use  the  cmake_pol-
       icy()  command  to  set it to OLD or NEW explicitly.  Unlike many poli-
       cies, CMake version 3.21.0 does not warn when this policy  is  not  set
       and simply uses OLD behavior.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0091
       New in version 3.15.


       MSVC runtime library flags are selected by an abstraction.

       Compilers targeting the MSVC ABI have flags to select the MSVC  runtime
       library.  Runtime library selection typically varies with build config-
       uration because there is a separate runtime library for Debug builds.

       In CMake 3.14 and below, MSVC runtime library selection flags are added
       to the default CMAKE_<LANG>_FLAGS_<CONFIG> cache entries by CMake auto-
       matically.  This allows users to edit their cache entries to adjust the
       flags.   However, the presence of such default flags is problematic for
       projects that want to choose a different runtime  library  programmati-
       cally.    In   particular,   it   requires   string   editing   of  the
       CMAKE_<LANG>_FLAGS_<CONFIG>  variables  with  knowledge  of  the  CMake
       builtin defaults so they can be replaced.

       CMake 3.15 and above prefer to leave the MSVC runtime library selection
       flags out of the default CMAKE_<LANG>_FLAGS_<CONFIG> values and instead
       offer  a first-class abstraction.  The CMAKE_MSVC_RUNTIME_LIBRARY vari-
       able and MSVC_RUNTIME_LIBRARY target property may be set to select  the
       MSVC  runtime library.  If they are not set then CMake uses the default
       value MultiThreaded$<$<CONFIG:Debug>:Debug>DLL which is  equivalent  to
       the original flags.

       This  policy  provides  compatibility  with projects that have not been
       updated to be aware of  the  abstraction.   The  policy  setting  takes
       effect  as  of  the  first  project() or enable_language() command that
       enables a language whose compiler targets the MSVC ABI.

       NOTE:
          Once the policy has taken effect at  the  top  of  a  project,  that
          choice  must  be  used  throughout  the tree.  In projects that have
          nested projects in subdirectories, be  sure  to  convert  everything
          together.

       The OLD behavior for this policy is to place MSVC runtime library flags
       in the default CMAKE_<LANG>_FLAGS_<CONFIG> cache entries and ignore the
       CMAKE_MSVC_RUNTIME_LIBRARY abstraction.  The NEW behavior for this pol-
       icy is to not place MSVC runtime library flags  in  the  default  cache
       entries and use the abstraction instead.

       This  policy  was introduced in CMake version 3.15.  Use the cmake_pol-
       icy() command to set it to OLD or NEW explicitly.   Unlike  many  poli-
       cies,  CMake  version  3.21.0 does not warn when this policy is not set
       and simply uses OLD behavior.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0090
       New in version 3.15.


       export(PACKAGE) does not populate package registry by default.

       In  CMake 3.14 and below the export(PACKAGE) command populated the user
       package  registry  by   default   and   users   needed   to   set   the
       CMAKE_EXPORT_NO_PACKAGE_REGISTRY to disable it, e.g. in automated build
       and packaging environments.  Since the user package registry is  stored
       outside  the  build  tree,  this  side  effect should not be enabled by
       default.  Therefore CMake 3.15 and above  prefer  that  export(PACKAGE)
       does  nothing unless an explicit CMAKE_EXPORT_PACKAGE_REGISTRY variable
       is set to enable it.  This policy provides compatibility with  projects
       that have not been updated.

       The OLD behavior for this policy is for export(PACKAGE) command to pop-
       ulate the user package registry unless CMAKE_EXPORT_NO_PACKAGE_REGISTRY
       is  enabled.   The  NEW  behavior  is for export(PACKAGE) command to do
       nothing unless the CMAKE_EXPORT_PACKAGE_REGISTRY is enabled.

       This policy was introduced in CMake version 3.15.  Use  the  cmake_pol-
       icy()  command  to  set it to OLD or NEW explicitly.  Unlike most poli-
       cies, CMake version 3.21.0 does not warn when this policy  is  not  set
       and simply uses OLD behavior.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0089
       New in version 3.15.


       Compiler id for IBM Clang-based XL compilers is now XLClang.

       CMake 3.15 and above recognize that IBM's Clang-based XL compilers that
       define __ibmxl__ are a new front-end distinct from xlc with a different
       command line and set of capabilities.  CMake  now  prefers  to  present
       this  to  projects  by setting the CMAKE_<LANG>_COMPILER_ID variable to
       XLClang instead of XL.  However, existing projects may assume the  com-
       piler  id  for  Clang-based  XL  is just XL as it was in CMake versions
       prior to 3.15.  Therefore this policy  determines  for  Clang-based  XL
       compilers  which  compiler id to report in the CMAKE_<LANG>_COMPILER_ID
       variable  after  language  <LANG>  is  enabled  by  the  project()   or
       enable_language() command.  The policy must be set prior to the invoca-
       tion of either command.

       The OLD behavior for this policy is to use compiler  id  XL.   The  NEW
       behavior for this policy is to use compiler id XLClang.

       This  policy  was introduced in CMake version 3.15.  Use the cmake_pol-
       icy() command to set this policy to OLD or NEW explicitly.  Unlike most
       policies,  CMake version 3.21.0 does not warn by default when this pol-
       icy is not set and simply uses OLD behavior.  See documentation of  the
       CMAKE_POLICY_WARNING_CMP0089 variable to control the warning.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.14
   CMP0088
       New in version 3.14.


       FindBISON runs bison in CMAKE_CURRENT_BINARY_DIR when executing.

       The module provides a BISON_TARGET macro which generates BISON  output.
       In  CMake 3.13 and below the macro would generate a custom command that
       runs bison in the source directory.  CMake 3.14 and later prefer to run
       it in the build directory and use CMAKE_CURRENT_BINARY_DIR as the WORK-
       ING_DIRECTORY of its  add_custom_command()  invocation.   This  ensures
       that  any implicitly generated file is written to the build tree rather
       than the source.

       This policy provides compatibility for  projects  that  have  not  been
       updated to expect the new behavior.

       The OLD behavior for this policy is for BISON_TARGET to use the current
       source directory  for  the  WORKING_DIRECTORY  and  where  to  generate
       implicit  files.  The NEW behavior of this policy is to use the current
       binary directory  for  the  WORKING_DIRECTORY  and  where  to  generate
       implicit files.

       This  policy  was introduced in CMake version 3.14.  Use the cmake_pol-
       icy() command to set it to OLD or NEW explicitly.   Unlike  most  poli-
       cies,  CMake  version  3.21.0 does not warn when this policy is not set
       and simply uses OLD behavior.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0087
       New in version 3.14.


       install(CODE) and install(SCRIPT) support generator expressions.

       In  CMake  3.13  and earlier, install(CODE) and install(SCRIPT) did not
       evaluate generator expressions.  CMake 3.14  and  later  will  evaluate
       generator expressions for install(CODE) and install(SCRIPT).

       The   OLD   behavior   of   this   policy   is  for  install(CODE)  and
       install(SCRIPT) to not evaluate generator expressions.  The NEW  behav-
       ior   is  to  evaluate  generator  expressions  for  install(CODE)  and
       install(SCRIPT).

       Note that it is the value of this policy setting  at  the  end  of  the
       directory  scope  that is important, not its setting at the time of the
       call to install(CODE) or install(SCRIPT).  This  has  implications  for
       calling these commands from places that have their own policy scope but
       not their own directory scope (e.g. from files brought in via include()
       rather than add_subdirectory()).

       This policy was introduced in CMake version 3.14.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0086
       New in version 3.14.


       UseSWIG honors SWIG_MODULE_NAME via -module flag.

       Starting with CMake 3.14, UseSWIG passes option  -module  <module_name>
       to  SWIG  compiler  if the file property SWIG_MODULE_NAME is specified.
       This policy provides compatibility with projects that expect the legacy
       behavior.

       The  OLD behavior for this policy is to never pass -module option.  The
       NEW behavior is to pass -module option to SWIG  compiler  if  SWIG_MOD-
       ULE_NAME is specified.

       This policy was introduced in CMake version 3.14.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0085
       New in version 3.14.


       $<IN_LIST:...> handles empty list items.

       In CMake 3.13 and lower, the $<IN_LIST:...> generator expression always
       returned  0 if the first argument was empty, even if the list contained
       an empty item. This behavior is inconsistent with the IN_LIST  behavior
       of  if(),  which  this  generator expression is meant to emulate. CMake
       3.14 and later handles this case correctly.

       The OLD behavior of this policy is for $<IN_LIST:...> to always  return
       0  if  the  first argument is empty. The NEW behavior is to return 1 if
       the first argument is empty and the list contains an empty item.

       This policy was introduced in CMake version 3.14.  CMake version 3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0084
       New in version 3.14.


       The FindQt module does not exist for find_package().

       The  existence  of FindQt means that for Qt upstream to provide package
       config files that can  be  found  by  find_package(Qt),  the  consuming
       project  has  to  explicitly  specify find_package(Qt CONFIG). Removing
       this module gives Qt a path forward for exporting its own config  files
       which can easily be found by consuming projects.

       This policy pretends that CMake's internal FindQt module does not exist
       for find_package(). If a project really wants to use Qt 3 or 4, it  can
       call  find_package(Qt[34]),  include(FindQt),  or  add  FindQt to their
       CMAKE_MODULE_PATH.

       The OLD behavior of this policy is for FindQt to exist  for  find_pack-
       age().  The  NEW  behavior  is  to  pretend  that  it doesn't exist for
       find_package().

       This policy was introduced in CMake version 3.14.  CMake version 3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0083
       New in version 3.14.


       To  control generation of Position Independent Executable (PIE) or not,
       some flags are required at link time.

       CMake 3.13 and lower did not add these link flags  when  POSITION_INDE-
       PENDENT_CODE is set.

       The  OLD  behavior for this policy is to not manage PIE link flags. The
       NEW behavior is to add link flags if POSITION_INDEPENDENT_CODE is set:

       o Set to TRUE: flags to produce a position independent  executable  are
         passed to the linker step. For example -pie for GCC.

       o Set  to FALSE: flags not to produce a position independent executable
         are passed to the linker step. For example -no-pie for GCC.

       o Not set: no flags are passed to the linker step.

       Since a given linker may not support PIE flags in all  environments  in
       which  it is used, it is the project's responsibility to use the Check-
       PIESupported module to check for  support  to  ensure  that  the  POSI-
       TION_INDEPENDENT_CODE  target  property for executables will be honored
       at link time.

       This policy was introduced in CMake version 3.14.  Use  the  cmake_pol-
       icy()  command  to  set it to OLD or NEW explicitly.  Unlike most poli-
       cies, CMake version 3.21.0 does not warn when this policy  is  not  set
       and simply uses OLD behavior.

       NOTE:
          Android platform has a special handling of PIE so it is not required
          to use the CheckPIESupported module to ensure flags  are  passed  to
          the linker.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   Examples
       Behave like CMake 3.13 and do not apply any PIE flags at link stage.

          cmake_minimum_required(VERSION 3.13)
          project(foo)

          # ...

          add_executable(foo ...)
          set_property(TARGET foo PROPERTY POSITION_INDEPENDENT_CODE TRUE)

       Use the CheckPIESupported module to detect whether PIE is supported  by
       the current linker and environment.  Apply PIE flags only if the linker
       supports them.

          cmake_minimum_required(VERSION 3.14) # CMP0083 NEW
          project(foo)

          include(CheckPIESupported)
          check_pie_supported()

          # ...

          add_executable(foo ...)
          set_property(TARGET foo PROPERTY POSITION_INDEPENDENT_CODE TRUE)

   CMP0082
       New in version 3.14.


       Install rules from add_subdirectory() calls are interleaved with  those
       in caller.

       CMake  3.13  and  lower  ran  the install rules from add_subdirectory()
       after all other install rules, even if  add_subdirectory()  was  called
       before  the other install rules.  CMake 3.14 and above prefer to inter-
       leave these add_subdirectory() install rules with the  others  so  that
       they are run in the order they are declared.  This policy provides com-
       patibility for projects that have not been updated to  expect  the  new
       behavior.

       The  OLD  behavior  for  this  policy  is to run the install rules from
       add_subdirectory() after the other install rules.  The NEW behavior for
       this policy is to run all install rules in the order they are declared.

       This  policy  was  introduced in CMake version 3.14.  Unlike most poli-
       cies, CMake version 3.21.0 does not warn by default when this policy is
       not  set  and  simply  uses  OLD  behavior.   See  documentation of the
       CMAKE_POLICY_WARNING_CMP0082 variable to control the warning.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.13
   CMP0081
       New in version 3.13.


       Relative paths not allowed in LINK_DIRECTORIES target property.

       CMake 3.12 and lower allowed the LINK_DIRECTORIES directory property to
       contain relative paths.  The base path for such relative entries is not
       well  defined.   CMake  3.13  and later will issue a FATAL_ERROR if the
       LINK_DIRECTORIES  target  property  (which  is   initialized   by   the
       LINK_DIRECTORIES directory property) contains a relative path.

       The OLD behavior for this policy is not to warn about relative paths in
       the LINK_DIRECTORIES target property.  The NEW behavior for this policy
       is to issue a FATAL_ERROR if LINK_DIRECTORIES contains a relative path.

       This policy was introduced in CMake version 3.13.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0080
       New in version 3.13.


       BundleUtilities cannot be included at configure time.

       The macros provided by BundleUtilities are intended to  be  invoked  at
       install  time rather than at configure time, because they depend on the
       listed targets already existing at the time they are invoked.  If  they
       are  invoked at configure time, the targets haven't been built yet, and
       the commands will fail.

       This policy restricts the inclusion  of  BundleUtilities  to  cmake  -P
       style  scripts  and install rules. Specifically, it looks for the pres-
       ence of CMAKE_GENERATOR and throws a fatal error if it exists.

       The OLD behavior of this policy  is  to  allow  BundleUtilities  to  be
       included  at configure time. The NEW behavior of this policy is to dis-
       allow such inclusion.

       This policy was introduced in CMake version 3.13.  CMake version 3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0079
       New in version 3.13.


       target_link_libraries() allows use with targets in other directories.

       Prior  to CMake 3.13 the target_link_libraries() command did not accept
       targets not created in the calling directory as its first argument  for
       calls  that  update  the  LINK_LIBRARIES  of the target itself.  It did
       accidentally accept targets from other directories on calls  that  only
       update  the  INTERFACE_LINK_LIBRARIES,  but would simply add entries to
       the property as if the call were made in the original directory.   Thus
       link  interface  libraries  specified this way were always looked up by
       generators in the scope of the original target rather than in the scope
       that called target_link_libraries().

       CMake  3.13 now allows the target_link_libraries() command to be called
       from  any  directory  to  add  link  dependencies  and  link  interface
       libraries  to  targets  created  in other directories.  The entries are
       added to LINK_LIBRARIES and INTERFACE_LINK_LIBRARIES  using  a  special
       (internal)  suffix  to  tell the generators to look up the names in the
       calling scope rather than the scope that created the target.

       This policy provides compatibility with projects that already use  tar-
       get_link_libraries()  with the INTERFACE keyword on a target in another
       directory to add INTERFACE_LINK_LIBRARIES entries to be  looked  up  in
       the target's directory.  Such projects should be updated to be aware of
       the new scoping rules in that case.

       The OLD behavior of this policy is to disallow  target_link_libraries()
       calls  naming  targets  from another directory except in the previously
       accidentally allowed case of using the INTERFACE keyword only.  The NEW
       behavior  of  this  policy  is  to allow all such calls but use the new
       scoping rules.

       This policy was introduced in CMake version 3.13.  CMake version 3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0078
       New in version 3.13.


       UseSWIG generates standard target names.

       Starting  with CMake 3.13, UseSWIG generates now standard target names.
       This policy provides compatibility with projects that expect the legacy
       behavior.

       The  OLD behavior for this policy relies on UseSWIG_TARGET_NAME_PREFER-
       ENCE variable that can be used to specify an explicit preference.   The
       value may be one of:

       o LEGACY:    legacy    strategy    is   applied.   Variable   SWIG_MOD-
         ULE_<name>_REAL_NAME must be used to get real target name.   This  is
         the default if not specified.

       o STANDARD: target name matches specified name.

       This policy was introduced in CMake version 3.13.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0077
       New in version 3.13.


       option() honors normal variables.

       The option() command is typically used to create a cache entry to allow
       users  to  set  the option.  However, there are cases in which a normal
       (non-cached) variable of the same name as the option may be defined  by
       the  project  prior  to  calling  the option() command.  For example, a
       project that embeds another project  as  a  subdirectory  may  want  to
       hard-code options of the subproject to build the way it needs.

       For  historical  reasons  in  CMake 3.12 and below the option() command
       removes a normal (non-cached) variable of the same name when:

       o a cache entry of the specified name does not exist at all, or

       o a cache entry of the specified name exists but has not been  given  a
         type (e.g. via -D<name>=ON on the command line).

       In  both  of  these  cases  (typically  on the first run in a new build
       tree), the option() command gives the cache entry type BOOL and removes
       any  normal  (non-cached)  variable of the same name.  In the remaining
       case that the cache entry of the specified name already exists and  has
       a  type (typically on later runs in a build tree), the option() command
       changes nothing and any normal variable of the same name remains set.

       In CMake 3.13 and above the option() command prefers to do nothing when
       a normal variable of the given name already exists.  It does not create
       or update a cache entry or remove the normal variable.  The new  behav-
       ior  is  consistent  between  the first and later runs in a build tree.
       This policy provides compatibility with projects  that  have  not  been
       updated to expect the new behavior.

       When the option() command sees a normal variable of the given name:

       o The  OLD  behavior  for  this policy is to proceed even when a normal
         variable of the same name  exists.   If  the  cache  entry  does  not
         already  exist and have a type then it is created and/or given a type
         and the normal variable is removed.

       o The NEW behavior for this policy is to do nothing when a normal vari-
         able  of  the  same name exists.  The normal variable is not removed.
         The cache entry is not created  or  updated  and  is  ignored  if  it
         exists.

       This policy was introduced in CMake version 3.13.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0076
       New in version 3.13.


       The target_sources() command converts relative paths to absolute.

       In CMake 3.13 and above, the target_sources() command now converts rel-
       ative source file paths to absolute paths in the following cases:

       o Source files are added to the target's INTERFACE_SOURCES property.

       o The    target's   SOURCE_DIR   property   differs   from   CMAKE_CUR-
         RENT_SOURCE_DIR.

       A path that begins with a generator expression is always  left  unmodi-
       fied.

       This  policy  provides  compatibility  with projects that have not been
       updated to expect this behavior.  The OLD behavior for this  policy  is
       to  leave  all relative source file paths unmodified.  The NEW behavior
       of this policy is to convert relative paths to  absolute  according  to
       above rules.

       This policy was introduced in CMake version 3.13.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.12
   CMP0075
       New in version 3.12.


       Include file check macros honor CMAKE_REQUIRED_LIBRARIES.

       In CMake 3.12 and above, the

       o check_include_file macro in the CheckIncludeFile module, the

       o check_include_file_cxx macro in the CheckIncludeFileCXX  module,  and
         the

       o check_include_files macro in the CheckIncludeFiles module

       now  prefer to link the check executable to the libraries listed in the
       CMAKE_REQUIRED_LIBRARIES variable.  This policy provides  compatibility
       with projects that have not been updated to expect this behavior.

       The  OLD behavior for this policy is to ignore CMAKE_REQUIRED_LIBRARIES
       in the include file check macros.  The NEW behavior of this  policy  is
       to honor CMAKE_REQUIRED_LIBRARIES in the include file check macros.

       This policy was introduced in CMake version 3.12.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0074
       New in version 3.12.


       find_package() uses <PackageName>_ROOT variables.

       In CMake 3.12 and above  the  find_package(<PackageName>)  command  now
       searches  prefixes  specified  by the <PackageName>_ROOT CMake variable
       and the <PackageName>_ROOT environment  variable.   Package  roots  are
       maintained  as  a  stack  so nested calls to all find_* commands inside
       find modules and config packages also search  the  roots  as  prefixes.
       This  policy  provides  compatibility  with projects that have not been
       updated to avoid using <PackageName>_ROOT variables for other purposes.

       The OLD behavior for this policy is to ignore <PackageName>_ROOT  vari-
       ables.   The  NEW behavior for this policy is to use <PackageName>_ROOT
       variables.

       This policy was introduced in CMake version 3.12.  CMake version 3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0073
       New in version 3.12.


       Do not produce legacy _LIB_DEPENDS cache entries.

       Ancient  CMake  versions  once  used <tgt>_LIB_DEPENDS cache entries to
       propagate library link dependencies.  This has long been done by  other
       means,  leaving  the  export_library_dependencies() command as the only
       user of these values.  That command has long been disallowed by  policy
       CMP0033, but the <tgt>_LIB_DEPENDS cache entries were left for compati-
       bility with possible non-standard uses by projects.

       CMake 3.12 and above now prefer to not produce these cache  entries  at
       all.   This  policy  provides compatibility with projects that have not
       been updated to avoid using them.

       The OLD behavior for this policy  is  to  set  <tgt>_LIB_DEPENDS  cache
       entries.  The NEW behavior for this policy is to not set them.

       This  policy  was introduced in CMake version 3.12.  Use the cmake_pol-
       icy() command to set it to OLD or NEW explicitly.   Unlike  most  poli-
       cies,  CMake  version  3.21.0 does not warn when this policy is not set
       and simply uses OLD behavior.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.11
   CMP0072
       New in version 3.11.


       FindOpenGL prefers GLVND by default when available.

       The   FindOpenGL   module   provides   an   OpenGL::GL  target  and  an
       OPENGL_LIBRARIES variable for projects to use for legacy GL interfaces.
       When  both  a legacy GL library (e.g. libGL.so) and GLVND libraries for
       OpenGL and GLX (e.g. libOpenGL.so and  libGLX.so)  are  available,  the
       module  must choose between them.  It documents an OpenGL_GL_PREFERENCE
       variable that can be used to specify an explicit preference.   When  no
       such preference is set, the module must choose a default preference.

       CMake  3.11  and  above  prefer to choose GLVND libraries.  This policy
       provides compatibility with projects that expect the legacy GL  library
       to be used.

       The  OLD  behavior  for  this  policy is to set OpenGL_GL_PREFERENCE to
       LEGACY.  The NEW behavior for this policy is to  set  OpenGL_GL_PREFER-
       ENCE to GLVND.

       This policy was introduced in CMake version 3.11.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.10
   CMP0071
       New in version 3.10.


       Let AUTOMOC and AUTOUIC process GENERATED files.

       Since version 3.10, CMake processes regular and GENERATED source  files
       in AUTOMOC and AUTOUIC.  In earlier CMake versions, only regular source
       files were processed.  GENERATED source files were ignored silently.

       This policy affects how source files that are GENERATED get treated  in
       AUTOMOC and AUTOUIC.

       The OLD behavior for this policy is to ignore GENERATED source files in
       AUTOMOC and AUTOUIC.

       The NEW behavior for this policy is to process GENERATED  source  files
       in AUTOMOC and AUTOUIC just like regular source files.

       NOTE:
          To  silence  the  CMP0071  warning source files can be excluded from
          AUTOMOC and AUTOUIC processing by setting the source file properties
          SKIP_AUTOMOC, SKIP_AUTOUIC or SKIP_AUTOGEN.

       Source skip example:

          # ...
          set_property(SOURCE /path/to/file1.h PROPERTY SKIP_AUTOMOC ON)
          set_property(SOURCE /path/to/file2.h PROPERTY SKIP_AUTOUIC ON)
          set_property(SOURCE /path/to/file3.h PROPERTY SKIP_AUTOGEN ON)
          # ...

       This policy was introduced in CMake version 3.10.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0070
       New in version 3.10.


       Define file(GENERATE) behavior for relative paths.

       CMake 3.10 and newer define that relative paths given to INPUT and OUT-
       PUT arguments of file(GENERATE) are interpreted relative to the current
       source and binary directories, respectively.  CMake 3.9 and  lower  did
       not  define  any  behavior for relative paths but did not diagnose them
       either and accidentally treated them relative to  the  process  working
       directory.   Policy  CMP0070  provides compatibility with projects that
       used the old undefined behavior.

       This policy affects behavior of relative paths given to file(GENERATE).
       The  OLD behavior for this policy is to treat the paths relative to the
       working directory of CMake.  The NEW behavior for  this  policy  is  to
       interpret  relative  paths with respect to the current source or binary
       directory of the caller.

       This policy was introduced in CMake version 3.10.  CMake version 3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.9
   CMP0069
       New in version 3.9.


       INTERPROCEDURAL_OPTIMIZATION is enforced when enabled.

       CMake  3.9 and newer prefer to add IPO flags whenever the INTERPROCEDU-
       RAL_OPTIMIZATION target property is enabled and  produce  an  error  if
       flags  are  not known to CMake for the current compiler.  Since a given
       compiler may not support IPO flags in all environments in which  it  is
       used,  it  is  now the project's responsibility to use the CheckIPOSup-
       ported module to check for support before  enabling  the  INTERPROCEDU-
       RAL_OPTIMIZATION  target  property.   This approach allows a project to
       conditionally activate IPO when supported.  It also allows an end  user
       to  set  the CMAKE_INTERPROCEDURAL_OPTIMIZATION variable in an environ-
       ment known to support IPO even if the project does not enable the prop-
       erty.

       Since CMake 3.8 and lower only honored INTERPROCEDURAL_OPTIMIZATION for
       the Intel compiler on Linux, some projects may  unconditionally  enable
       the  target  property.  Policy CMP0069 provides compatibility with such
       projects.

       This policy takes effect whenever the IPO property is enabled.  The OLD
       behavior for this policy is to add IPO flags only for Intel compiler on
       Linux.  The NEW behavior for this policy is to add IPO  flags  for  the
       current compiler or produce an error if CMake does not know the flags.

       This  policy was introduced in CMake version 3.9.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   Examples
       Behave like CMake 3.8 and do not apply any IPO flags except  for  Intel
       compiler on Linux:

          cmake_minimum_required(VERSION 3.8)
          project(foo)

          # ...

          set_property(TARGET ... PROPERTY INTERPROCEDURAL_OPTIMIZATION TRUE)

       Use  the CheckIPOSupported module to detect whether IPO is supported by
       the current compiler, environment, and CMake version.  Produce a  fatal
       error if support is not available:

          cmake_minimum_required(VERSION 3.9) # CMP0069 NEW
          project(foo)

          include(CheckIPOSupported)
          check_ipo_supported()

          # ...

          set_property(TARGET ... PROPERTY INTERPROCEDURAL_OPTIMIZATION TRUE)

       Apply IPO flags only if compiler supports it:

          cmake_minimum_required(VERSION 3.9) # CMP0069 NEW
          project(foo)

          include(CheckIPOSupported)

          # ...

          check_ipo_supported(RESULT result)
          if(result)
            set_property(TARGET ... PROPERTY INTERPROCEDURAL_OPTIMIZATION TRUE)
          endif()

       Apply  IPO  flags without any checks.  This may lead to build errors if
       IPO is not supported by the compiler in the current environment.   Pro-
       duce  an  error  if  CMake does not know IPO flags for the current com-
       piler:

          cmake_minimum_required(VERSION 3.9) # CMP0069 NEW
          project(foo)

          # ...

          set_property(TARGET ... PROPERTY INTERPROCEDURAL_OPTIMIZATION TRUE)

   CMP0068
       New in version 3.9.


       RPATH settings on macOS do not affect install_name.

       CMake 3.9 and newer remove any effect the following settings  may  have
       on the install_name of a target on macOS:

       o BUILD_WITH_INSTALL_RPATH target property

       o SKIP_BUILD_RPATH target property

       o CMAKE_SKIP_RPATH variable

       o CMAKE_SKIP_INSTALL_RPATH variable

       Previously,  setting BUILD_WITH_INSTALL_RPATH had the effect of setting
       both the install_name of a target to INSTALL_NAME_DIR and the RPATH  to
       INSTALL_RPATH.   In  CMake 3.9, it only affects setting of RPATH.  How-
       ever, if one wants INSTALL_NAME_DIR to apply to the target in the build
       tree, one may set BUILD_WITH_INSTALL_NAME_DIR.

       If  SKIP_BUILD_RPATH, CMAKE_SKIP_RPATH or CMAKE_SKIP_INSTALL_RPATH were
       used to strip the directory portion of the install_name  of  a  target,
       one may set INSTALL_NAME_DIR="" instead.

       The  OLD  behavior  of  this  policy  is  to use the RPATH settings for
       install_name on macOS.  The NEW behavior of this policy  is  to  ignore
       the RPATH settings for install_name on macOS.

       This  policy was introduced in CMake version 3.9.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.8
   CMP0067
       New in version 3.8.


       Honor language standard in try_compile() source-file signature.

       The try_compile() source file signature is intended to allow callers to
       check whether they will be able to compile a given source file with the
       current toolchain.  In order to match compiler behavior,  any  language
       standard  mode  should  match.  However, CMake 3.7 and below did not do
       this.  CMake 3.8 and above prefer to honor the language  standard  set-
       tings for C, CXX (C++), and CUDA using the values of the variables:

       o CMAKE_C_STANDARD

       o CMAKE_C_STANDARD_REQUIRED

       o CMAKE_C_EXTENSIONS

       o CMAKE_CXX_STANDARD

       o CMAKE_CXX_STANDARD_REQUIRED

       o CMAKE_CXX_EXTENSIONS

       o CMAKE_CUDA_STANDARD

       o CMAKE_CUDA_STANDARD_REQUIRED

       o CMAKE_CUDA_EXTENSIONS

       This  policy provides compatibility for projects that do not expect the
       language standard settings to be used automatically.

       The OLD behavior of this policy is to ignore language standard  setting
       variables when generating the try_compile test project.  The NEW behav-
       ior of this policy is to honor language standard setting variables.

       This policy was introduced in CMake version 3.8.  Unlike most policies,
       CMake  version  3.21.0 does not warn by default when this policy is not
       set and simply uses OLD behavior.  See documentation of the  CMAKE_POL-
       ICY_WARNING_CMP0067 variable to control the warning.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.7
   CMP0066
       New in version 3.7.


       Honor per-config flags in try_compile() source-file signature.

       The source file signature of the try_compile() command uses  the  value
       of the CMAKE_<LANG>_FLAGS variable in the test project so that the test
       compilation works as it would in the main project.  However, CMake  3.6
       and  below  do  not  also  honor config-specific compiler flags such as
       those in the CMAKE_<LANG>_FLAGS_DEBUG variable.  CMake  3.7  and  above
       prefer  to  honor config-specific compiler flags too.  This policy pro-
       vides compatibility for projects that  do  not  expect  config-specific
       compiler flags to be used.

       The OLD behavior of this policy is to ignore config-specific flag vari-
       ables like  CMAKE_<LANG>_FLAGS_DEBUG  and  only  use  CMake's  built-in
       defaults for the current compiler and platform.

       The  NEW behavior of this policy is to honor config-specific flag vari-
       abldes like CMAKE_<LANG>_FLAGS_DEBUG.

       This policy was introduced in CMake version 3.7.  Unlike most policies,
       CMake  version  3.21.0 does not warn by default when this policy is not
       set and simply uses OLD behavior.  See documentation of the  CMAKE_POL-
       ICY_WARNING_CMP0066 variable to control the warning.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.4
   CMP0065
       New in version 3.4.


       Do not add  flags  to  export  symbols  from  executables  without  the
       ENABLE_EXPORTS target property.

       CMake  3.3 and below, for historical reasons, always linked executables
       on some platforms with flags like -rdynamic to export symbols from  the
       executables for use by any plugins they may load via dlopen.  CMake 3.4
       and above prefer to do this only for executables  that  are  explicitly
       marked with the ENABLE_EXPORTS target property.

       The  OLD  behavior  of this policy is to always use the additional link
       flags  when  linking  executables  regardless  of  the  value  of   the
       ENABLE_EXPORTS target property.

       The  NEW  behavior  of  this  policy is to only use the additional link
       flags when linking executables if the ENABLE_EXPORTS target property is
       set to True.

       This policy was introduced in CMake version 3.4.  Unlike most policies,
       CMake version 3.21.0 does not warn by default when this policy  is  not
       set  and simply uses OLD behavior.  See documentation of the CMAKE_POL-
       ICY_WARNING_CMP0065 variable to control the warning.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0064
       New in version 3.4.


       Recognize TEST as a operator for the if() command.

       The TEST operator was added to the if() command to determine if a given
       test name was created by the add_test() command.

       The OLD behavior for this policy is to ignore the TEST  operator.   The
       NEW behavior is to interpret the TEST operator.

       This  policy was introduced in CMake version 3.4.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.3
   CMP0063
       New in version 3.3.


       Honor visibility properties for all target types.

       The <LANG>_VISIBILITY_PRESET and VISIBILITY_INLINES_HIDDEN target prop-
       erties affect visibility of symbols during dynamic linking.  When first
       introduced these properties affected compilation  of  sources  only  in
       shared   libraries,   module   libraries,   and  executables  with  the
       ENABLE_EXPORTS property set.  This was sufficient  for  the  basic  use
       cases  of shared libraries and executables with plugins.  However, some
       sources may be compiled as part of static libraries or object libraries
       and  then linked into a shared library later.  CMake 3.3 and above pre-
       fer to honor these properties for sources compiled in all target types.
       This  policy preserves compatibility for projects expecting the proper-
       ties to work only for some target types.

       The OLD behavior for this policy is to ignore the visibility properties
       for   static  libraries,  object  libraries,  and  executables  without
       exports.  The NEW behavior for this policy is to honor  the  visibility
       properties for all target types.

       This  policy was introduced in CMake version 3.3.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0062
       New in version 3.3.


       Disallow install() of export() result.

       The export() command generates  a  file  containing  Imported  Targets,
       which is suitable for use from the build directory.  It is not suitable
       for installation because it  contains  absolute  paths  to  buildsystem
       locations, and is particular to a single build configuration.

       The install(EXPORT) generates and installs files which contain Imported
       Targets.  These files are generated with  relative  paths  (unless  the
       user  specifies  absolute paths), and are designed for multi-configura-
       tion use.  See Creating Packages for more.

       CMake 3.3 no longer allows the use of the install(FILES)  command  with
       the result of the export() command.

       The  OLD  behavior for this policy is to allow installing the result of
       an export() command.  The NEW behavior for this policy is not to  allow
       installing the result of an export() command.

       This  policy was introduced in CMake version 3.3.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0061
       New in version 3.3.


       CTest does not by default tell make to ignore errors (-i).

       The ctest_build() and build_command() commands no longer generate build
       commands  for  Makefile Generators with the -i option.  Previously this
       was done to help build as much of tested projects  as  possible.   How-
       ever,  this  behavior  is not consistent with other generators and also
       causes the return code of the make tool to be meaningless.

       Of  course  users  may  still  add  this  option  manually  by  setting
       CTEST_BUILD_COMMAND  or  the  MAKECOMMAND  cache  entry.  See the CTest
       Build Step MakeCommand setting documentation for their effects.

       The OLD behavior for this policy is to add -i to make calls  in  CTest.
       The NEW behavior for this policy is to not add -i.

       This policy was introduced in CMake version 3.3.  Unlike most policies,
       CMake version 3.21.0 does not warn when this policy is not set and sim-
       ply uses OLD behavior.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0060
       New in version 3.3.


       Link libraries by full path even in implicit directories.

       Policy CMP0003 was introduced with  the  intention  of  always  linking
       library  files  by  full  path  when  a  full path is given to the tar-
       get_link_libraries() command.  However, on some platforms (e.g.  HP-UX)
       the  compiler  front-end  adds alternative library search paths for the
       current  architecture  (e.g.  /usr/lib/<arch>   has   alternatives   to
       libraries in /usr/lib for the current architecture).  On such platforms
       the find_library() may find a library such as  /usr/lib/libfoo.so  that
       does not belong to the current architecture.

       Prior  to  policy  CMP0003  projects  would  still  build in such cases
       because the incorrect library path would be converted to -lfoo  on  the
       link line and the linker would find the proper library in the arch-spe-
       cific search path provided by the compiler  front-end  implicitly.   At
       the  time  we  chose  to remain compatible with such projects by always
       converting library files found in implicit link  directories  to  -lfoo
       flags  to  ask  the  linker  to search for them.  This approach allowed
       existing projects to continue to build while still linking to libraries
       outside  implicit  link directories via full path (such as those in the
       build tree).

       CMake does allow  projects  to  override  this  behavior  by  using  an
       IMPORTED  library target with its IMPORTED_LOCATION property set to the
       desired full path to a library file.  In fact, many  Find  Modules  are
       learning  to  provide  Imported Targets instead of just the traditional
       Foo_LIBRARIES variable listing library files.  However, this makes  the
       link  line  generated  for  a  library found by a Find Module depend on
       whether it is linked through an imported target or not, which is incon-
       sistent.   Furthermore,  this  behavior  has been a source of confusion
       because the generated link line for a library file depends on its loca-
       tion.   It  is  also problematic for projects trying to link statically
       because flags like -Wl,-Bstatic -lfoo -Wl,-Bdynamic may be used to help
       the  linker  select libfoo.a instead of libfoo.so but then leak dynamic
       linking to following libraries.  (See the LINK_SEARCH_END_STATIC target
       property for a solution typically used for that problem.)

       When  the  special  case for libraries in implicit link directories was
       first introduced the list  of  implicit  link  directories  was  simply
       hard-coded  (e.g.  /lib, /usr/lib, and a few others).  Since that time,
       CMake has learned to detect the implicit link directories used  by  the
       compiler  front-end.  If necessary, the find_library() command could be
       taught to use this information to help find  libraries  of  the  proper
       architecture.

       For  these reasons, CMake 3.3 and above prefer to drop the special case
       and link libraries by full path even when they  are  in  implicit  link
       directories.    Policy  CMP0060  provides  compatibility  for  existing
       projects.

       The OLD behavior for this policy is to ask the  linker  to  search  for
       libraries  whose  full  paths are known to be in implicit link directo-
       ries.  The NEW behavior for this policy is to link  libraries  by  full
       path even if they are in implicit link directories.

       This policy was introduced in CMake version 3.3.  Unlike most policies,
       CMake version 3.21.0 does not warn by default when this policy  is  not
       set  and simply uses OLD behavior.  See documentation of the CMAKE_POL-
       ICY_WARNING_CMP0060 variable to control the warning.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0059
       New in version 3.3.


       Do not treat DEFINITIONS as a built-in directory property.

       CMake  3.3  and  above  no  longer make a list of definitions available
       through the DEFINITIONS directory  property.   The  COMPILE_DEFINITIONS
       directory property may be used instead.

       The  OLD behavior for this policy is to provide the list of flags given
       so far to the add_definitions() command.  The NEW behavior is to behave
       as a normal user-defined directory property.

       This  policy was introduced in CMake version 3.3.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0058
       New in version 3.3.


       Ninja requires custom command byproducts to be explicit.

       When an intermediate file generated during the build is consumed by  an
       expensive  operation  or a large tree of dependents, one may reduce the
       work needed for an incremental rebuild by updating the  file  timestamp
       only  when its content changes.  With this approach the generation rule
       must have a separate output file that is  always  updated  with  a  new
       timestamp  that  is newer than any dependencies of the rule so that the
       build tool re-runs the rule only when the input changes.  We  refer  to
       the  separate output file as a rule's witness and the generated file as
       a rule's byproduct.

       Byproducts may not be listed as outputs because  their  timestamps  are
       allowed  to  be older than the inputs.  No build tools (like make) that
       existed when CMake was designed  have  a  way  to  express  byproducts.
       Therefore  CMake  versions  prior  to  3.2  had no way to specify them.
       Projects typically left byproducts undeclared in the rules that  gener-
       ate them.  For example:

          add_custom_command(
            OUTPUT witness.txt
            COMMAND ${CMAKE_COMMAND} -E copy_if_different
                    ${CMAKE_CURRENT_SOURCE_DIR}/input.txt
                    byproduct.txt # timestamp may not change
            COMMAND ${CMAKE_COMMAND} -E touch witness.txt
            DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/input.txt
            )
          add_custom_target(Provider DEPENDS witness.txt)
          add_custom_command(
            OUTPUT generated.c
            COMMAND expensive-task -i byproduct.txt -o generated.c
            DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/byproduct.txt
            )
          add_library(Consumer generated.c)
          add_dependencies(Consumer Provider)

       This  works well for all generators except Ninja.  The Ninja build tool
       sees a rule listing byproduct.txt as a dependency and no  rule  listing
       it  as an output.  Ninja then complains that there is no way to satisfy
       the dependency and stops building  even  though  there  are  order-only
       dependencies  that ensure byproduct.txt will exist before its consumers
       need it.  See discussion of this problem in Ninja Issue 760 for further
       details on why Ninja works this way.

       Instead  of  leaving  byproducts  undeclared in the rules that generate
       them, Ninja expects byproducts to be listed along with  other  outputs.
       Such rules may be marked with a restat option that tells Ninja to check
       the timestamps of outputs after the rules run.  This  prevents  byprod-
       ucts  whose  timestamps  do not change from causing their dependents to
       re-build unnecessarily.

       Since the above approach does not tell CMake what custom command gener-
       ates  byproduct.txt,  the Ninja generator does not have enough informa-
       tion to add the byproduct as an output of any rule.  CMake  2.8.12  and
       above  work  around  this  problem  and  allow projects using the above
       approach to build by generating phony build rules to tell Ninja to tol-
       erate such missing files.  However, this workaround prevents Ninja from
       diagnosing a dependency that is really missing.  It also  works  poorly
       in  in-source  builds  where  every  custom command dependency, even on
       source files, needs to be treated this way because CMake does not  have
       enough  information  to know which files are generated as byproducts of
       custom commands.

       CMake 3.2 introduced the BYPRODUCTS option to the  add_custom_command()
       and  add_custom_target() commands.  This option allows byproducts to be
       specified explicitly:

          add_custom_command(
            OUTPUT witness.txt
            BYPRODUCTS byproduct.txt # explicit byproduct specification
            COMMAND ${CMAKE_COMMAND} -E copy_if_different
                    ${CMAKE_CURRENT_SOURCE_DIR}/input.txt
                    byproduct.txt # timestamp may not change
          ...

       The BYPRODUCTS option is used by the Ninja generator to list byproducts
       among  the  outputs  of  the custom commands that generate them, and is
       ignored by other generators.

       CMake 3.3 and above prefer to require projects to specify  custom  com-
       mand  byproducts  explicitly  so that it can avoid using the phony rule
       workaround altogether.  Policy CMP0058 was introduced to  provide  com-
       patibility with existing projects that still need the workaround.

       This  policy  has  no  effect  on generators other than Ninja.  The OLD
       behavior for this policy is to generate Ninja phony rules  for  unknown
       dependencies in the build tree.  The NEW behavior for this policy is to
       not generate these and instead require projects to specify custom  com-
       mand BYPRODUCTS explicitly.

       This  policy was introduced in CMake version 3.3.  CMake version 3.21.0
       warns when it sees unknown dependencies in out-of-source build trees if
       the  policy  is not set and then uses OLD behavior.  Use the cmake_pol-
       icy() command to set the policy to OLD or NEW explicitly.   The  policy
       setting  must  be  in  scope at the end of the top-level CMakeLists.txt
       file of the project and has global effect.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0057
       New in version 3.3.


       Support new if() IN_LIST operator.

       CMake 3.3 adds support for the new IN_LIST operator.

       The  OLD  behavior  for  this policy is to ignore the IN_LIST operator.
       The NEW behavior is to interpret the IN_LIST operator.

       This policy was introduced in CMake version 3.3.  CMake version  3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.2
   CMP0056
       New in version 3.2.


       Honor link flags in try_compile() source-file signature.

       The  try_compile()  command  source-file  signature  generates a CMake-
       Lists.txt file to build the source file into an executable.   In  order
       to compile the source the same way as it might be compiled by the call-
       ing  project,  the  generated   project   sets   the   value   of   the
       CMAKE_<LANG>_FLAGS  variable to that in the calling project.  The value
       of the CMAKE_EXE_LINKER_FLAGS variable may be needed in some cases too,
       but CMake 3.1 and lower did not set it in the generated project.  CMake
       3.2 and above prefer to set it so that linker flags are honored as well
       as compiler flags.  This policy provides compatibility with the pre-3.2
       behavior.

       The OLD behavior for this policy  is  to  not  set  the  value  of  the
       CMAKE_EXE_LINKER_FLAGS variable in the generated test project.  The NEW
       behavior   for   this   policy   is   to   set   the   value   of   the
       CMAKE_EXE_LINKER_FLAGS  variable  in the test project to the same as it
       is in the calling project.

       If the project code does not set the policy explicitly, users  may  set
       it  on  the  command  line by defining the CMAKE_POLICY_DEFAULT_CMP0056
       variable in the cache.

       This policy was introduced in CMake version 3.2.  Unlike most policies,
       CMake  version  3.21.0 does not warn by default when this policy is not
       set and simply uses OLD behavior.  See documentation of the  CMAKE_POL-
       ICY_WARNING_CMP0056 variable to control the warning.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0055
       New in version 3.2.


       Strict checking for the break() command.

       CMake 3.1 and lower allowed calls to the break() command outside  of  a
       loop  context and also ignored any given arguments.  This was undefined
       behavior.

       The OLD behavior for this policy is to allow break() to be placed  out-
       side  of loop contexts and ignores any arguments.  The NEW behavior for
       this policy is to issue an error if a misplaced break or any  arguments
       are found.

       This  policy was introduced in CMake version 3.2.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.1
   CMP0054
       New in version 3.1.


       Only interpret if() arguments as variables or keywords when unquoted.

       CMake 3.1 and above  no  longer  implicitly  dereference  variables  or
       interpret  keywords  in  an  if()  command argument when it is a Quoted
       Argument or a Bracket Argument.

       The OLD behavior for this policy is to dereference variables and inter-
       pret  keywords  even if they are quoted or bracketed.  The NEW behavior
       is to not dereference variables or interpret keywords  that  have  been
       quoted or bracketed.

       Given the following partial example:

          set(A E)
          set(E "")

          if("${A}" STREQUAL "")
            message("Result is TRUE before CMake 3.1 or when CMP0054 is OLD")
          else()
            message("Result is FALSE in CMake 3.1 and above if CMP0054 is NEW")
          endif()

       After explicit expansion of variables this gives:

          if("E" STREQUAL "")

       With the policy set to OLD implicit expansion reduces this semantically
       to:

          if("" STREQUAL "")

       With the policy set to NEW the quoted arguments  will  not  be  further
       dereferenced:

          if("E" STREQUAL "")

       This  policy was introduced in CMake version 3.1.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0053
       New in version 3.1.


       Simplify variable reference and escape sequence evaluation.

       CMake 3.1 introduced a much faster implementation of evaluation of  the
       Variable  References  and Escape Sequences documented in the cmake-lan-
       guage(7) manual.  While the behavior is identical to the legacy  imple-
       mentation  in most cases, some corner cases were cleaned up to simplify
       the behavior.  Specifically:

       o Expansion of @VAR@ reference syntax defined by  the  configure_file()
         and  string(CONFIGURE)  commands is no longer performed in other con-
         texts.

       o Literal ${VAR} reference syntax may contain only alphanumeric charac-
         ters (A-Z, a-z, 0-9) and the characters _, ., /, -, and +.  Note that
         $ is technically allowed in the NEW behavior, but is invalid for  OLD
         behavior.   This  is due to an oversight during the implementation of
         CMP0053 and its use as a literal variable  reference  is  discouraged
         for  this  reason.  Variables with other characters in their name may
         still be referenced indirectly, e.g.

            set(varname "otherwise & disallowed $ characters")
            message("${${varname}}")

       o The setting of policy CMP0010 is not considered, so improper variable
         reference syntax is always an error.

       o More  characters are allowed to be escaped in variable names.  Previ-
         ously, only ()#"  \@^  were  valid  characters  to  escape.  Now  any
         non-alphanumeric,  non-semicolon,  non-NUL  character  may be escaped
         following the escape_identity production in the Escape Sequences sec-
         tion of the cmake-language(7) manual.

       The  OLD  behavior  for this policy is to honor the legacy behavior for
       variable references and escape sequences.  The NEW behavior is  to  use
       the simpler variable expansion and escape sequence evaluation rules.

       This  policy was introduced in CMake version 3.1.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0052
       New in version 3.1.


       Reject source and build dirs  in  installed  INTERFACE_INCLUDE_DIRECTO-
       RIES.

       CMake  3.0  and lower allowed subdirectories of the source directory or
       build directory to be in the INTERFACE_INCLUDE_DIRECTORIES of installed
       and  exported  targets, if the directory was also a subdirectory of the
       installation prefix.  This makes the installation depend on  the  exis-
       tence  of  the  source  dir or binary dir, and the installation will be
       broken if either are removed after installation.

       See Include Directories and Usage Requirements for more  on  specifying
       include directories for targets.

       The OLD behavior for this policy is to export the content of the INTER-
       FACE_INCLUDE_DIRECTORIES with the source or binary directory.  The  NEW
       behavior  for  this  policy is to issue an error if such a directory is
       used.

       This policy was introduced in CMake version 3.1.  CMake version  3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0051
       New in version 3.1.


       List TARGET_OBJECTS in SOURCES target property.

       CMake  3.0  and  lower  did  not  include  the TARGET_OBJECTS generator
       expression when returning the SOURCES target property.

       Configure-time CMake code is not able to handle generator  expressions.
       If  using the SOURCES target property at configure time, it may be nec-
       essary   to   first   remove   generator    expressions    using    the
       string(GENEX_STRIP)   command.    Generate-time   CMake  code  such  as
       file(GENERATE) can handle the content without stripping.

       The OLD behavior for this policy is to omit TARGET_OBJECTS  expressions
       from  the SOURCES target property.  The NEW behavior for this policy is
       to include TARGET_OBJECTS expressions in the output.

       This policy was introduced in CMake version 3.1.  CMake version  3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 3.0
   CMP0050
       Disallow add_custom_command SOURCE signatures.

       CMake  2.8.12  and  lower  allowed a signature for add_custom_command()
       which specified an input to a command.  This was undocumented behavior.
       Modern  use  of  CMake  associates  custom  commands with their output,
       rather than their input.

       The OLD behavior for this policy is to allow the use of add_custom_com-
       mand() SOURCE signatures.  The NEW behavior for this policy is to issue
       an error if such a signature is used.

       This policy was introduced in CMake version 3.0.  CMake version  3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0049
       Do not expand variables in target source entries.

       CMake  2.8.12  and lower performed an extra layer of variable expansion
       when evaluating source file names:

          set(a_source foo.c)
          add_executable(foo \${a_source})

       This was undocumented behavior.

       The OLD behavior for this policy is to expand such variables when  pro-
       cessing  the  target  sources.   The NEW behavior for this policy is to
       issue an error if such variables need to be expanded.

       This policy was introduced in CMake version 3.0.  CMake version  3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0048
       The project() command manages VERSION variables.

       CMake  version  3.0 introduced the VERSION option of the project() com-
       mand to specify a project version as well as the  name.   In  order  to
       keep  PROJECT_VERSION  and  related  variables consistent with variable
       PROJECT_NAME it is necessary to set the VERSION variables to the  empty
       string when no VERSION is given to project().  However, this can change
       behavior for existing projects that set  VERSION  variables  themselves
       since  project() may now clear them.  This policy controls the behavior
       for compatibility with such projects.

       The OLD  behavior  for  this  policy  is  to  leave  VERSION  variables
       untouched.  The NEW behavior for this policy is to set VERSION as docu-
       mented by the project() command.

       This policy was introduced in CMake version 3.0.  CMake version  3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0047
       Use QCC compiler id for the qcc drivers on QNX.

       CMake  3.0 and above recognize that the QNX qcc compiler driver is dif-
       ferent from the GNU compiler.  CMake now prefers  to  present  this  to
       projects  by  setting  the  CMAKE_<LANG>_COMPILER_ID  variable  to  QCC
       instead of GNU.  However, existing projects may assume the compiler  id
       for  QNX  qcc  is  just  GNU  as it was in CMake versions prior to 3.0.
       Therefore this policy determines for  QNX  qcc  which  compiler  id  to
       report  in  the CMAKE_<LANG>_COMPILER_ID variable after language <LANG>
       is enabled by the project() or enable_language() command.   The  policy
       must be set prior to the invocation of either command.

       The  OLD behavior for this policy is to use the GNU compiler id for the
       qcc and QCC compiler drivers. The NEW behavior for this  policy  is  to
       use the QCC compiler id for those drivers.

       This  policy  was  introduced in CMake version 3.0.  Use the cmake_pol-
       icy() command to set this policy to OLD or NEW explicitly.  Unlike most
       policies,  CMake version 3.21.0 does not warn by default when this pol-
       icy is not set and simply uses OLD behavior.  See documentation of  the
       CMAKE_POLICY_WARNING_CMP0047 variable to control the warning.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0046
       Error on non-existent dependency in add_dependencies.

       CMake 2.8.12  and  lower  silently  ignored  non-existent  dependencies
       listed in the add_dependencies() command.

       The  OLD  behavior  for  this policy is to silently ignore non-existent
       dependencies. The NEW behavior for this policy is to report an error if
       non-existent dependencies are listed in the add_dependencies() command.

       This  policy was introduced in CMake version 3.0.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0045
       Error on non-existent target in get_target_property.

       In CMake 2.8.12 and lower, the get_target_property() command accepted a
       non-existent target argument without issuing any error or warning.  The
       result variable is set to a -NOTFOUND value.

       The OLD behavior for this policy is to issue no  warning  and  set  the
       result variable to a -NOTFOUND value.  The NEW behavior for this policy
       is to issue a FATAL_ERROR if the command is called with a  non-existent
       target.

       This  policy was introduced in CMake version 3.0.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0044
       Case sensitive <LANG>_COMPILER_ID generator expressions

       CMake 2.8.12 introduced the <LANG>_COMPILER_ID generator expressions to
       allow  comparison  of  the  CMAKE_<LANG>_COMPILER_ID with a test value.
       The possible valid values are lowercase, but the  comparison  with  the
       test value was performed case-insensitively.

       The  OLD behavior for this policy is to perform a case-insensitive com-
       parison with the value in the <LANG>_COMPILER_ID  expression.  The  NEW
       behavior for this policy is to perform a case-sensitive comparison with
       the value in the <LANG>_COMPILER_ID expression.

       This policy was introduced in CMake version 3.0.  CMake version  3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0043
       Ignore COMPILE_DEFINITIONS_<Config> properties

       CMake 2.8.12 and lower allowed setting the COMPILE_DEFINITIONS_<CONFIG>
       target property and COMPILE_DEFINITIONS_<CONFIG> directory property  to
       apply configuration-specific compile definitions.

       Since CMake 2.8.10, the COMPILE_DEFINITIONS property has supported gen-
       erator expressions for setting  configuration-dependent  content.   The
       continued  existence of the suffixed variables is redundant, and causes
       a maintenance  burden.   Population  of  the  COMPILE_DEFINITIONS_DEBUG
       property  may  be  replaced  with  a  population of COMPILE_DEFINITIONS
       directly or via target_compile_definitions():

          # Old Interfaces:
          set_property(TARGET tgt APPEND PROPERTY
            COMPILE_DEFINITIONS_DEBUG DEBUG_MODE
          )
          set_property(DIRECTORY APPEND PROPERTY
            COMPILE_DEFINITIONS_DEBUG DIR_DEBUG_MODE
          )

          # New Interfaces:
          set_property(TARGET tgt APPEND PROPERTY
            COMPILE_DEFINITIONS $<$<CONFIG:Debug>:DEBUG_MODE>
          )
          target_compile_definitions(tgt PRIVATE $<$<CONFIG:Debug>:DEBUG_MODE>)
          set_property(DIRECTORY APPEND PROPERTY
            COMPILE_DEFINITIONS $<$<CONFIG:Debug>:DIR_DEBUG_MODE>
          )

       The OLD behavior for this policy is to consume the content of the  suf-
       fixed  COMPILE_DEFINITIONS_<CONFIG> target property when generating the
       compilation command. The NEW behavior for this policy is to ignore  the
       content of the COMPILE_DEFINITIONS_<CONFIG> target property .

       This  policy was introduced in CMake version 3.0.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0042
       MACOSX_RPATH is enabled by default.

       CMake 2.8.12 and newer has support  for  using  @rpath  in  a  target's
       install  name.   This  was  enabled  by  setting  the  target  property
       MACOSX_RPATH.  The @rpath in an install name is  a  more  flexible  and
       powerful  mechanism  than @executable_path or @loader_path for locating
       shared libraries.

       CMake 3.0 and later prefer this property to be ON by default.  Projects
       wanting @rpath in a target's install name may remove any setting of the
       INSTALL_NAME_DIR and CMAKE_INSTALL_NAME_DIR variables.

       This policy was introduced in CMake version 3.0.  CMake version  3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0041
       Error on relative include with generator expression.

       Diagnostics  in CMake 2.8.12 and lower silently ignored an entry in the
       INTERFACE_INCLUDE_DIRECTORIES of a target if it contained  a  generator
       expression at any position.

       The  path  entries  in  that  target  property  should not be relative.
       High-level API should ensure that by adding either a  source  directory
       or a install directory prefix, as appropriate.

       As  an  additional diagnostic, the INTERFACE_INCLUDE_DIRECTORIES gener-
       ated on an IMPORTED target for the install location should not  contain
       paths in the source directory or the build directory.

       The  OLD behavior for this policy is to ignore relative path entries if
       they contain a generator expression. The NEW behavior for  this  policy
       is  to  report  an  error  if a generator expression appears in another
       location and the path is relative.

       This policy was introduced in CMake version 3.0.  CMake version  3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0040
       The  target  in the TARGET signature of add_custom_command() must exist
       and must be defined in the current directory.

       CMake 2.8.12 and lower silently ignored a custom command  created  with
       the  TARGET  signature of add_custom_command() if the target is unknown
       or was defined outside the current directory.

       The OLD behavior for this policy  is  to  ignore  custom  commands  for
       unknown  targets.   The  NEW  behavior  for this policy is to report an
       error if the target referenced in add_custom_command()  is  unknown  or
       was defined outside the current directory.

       This  policy was introduced in CMake version 3.0.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0039
       Utility targets may not have link dependencies.

       CMake 2.8.12 and lower allowed using utility targets in the  left  hand
       side  position of the target_link_libraries() command. This is an indi-
       cator of a bug in user code.

       The OLD behavior for this policy is to ignore attempts to set the  link
       libraries  of  utility targets.  The NEW behavior for this policy is to
       report an error if an attempt is made to set the link  libraries  of  a
       utility target.

       This  policy was introduced in CMake version 3.0.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0038
       Targets may not link directly to themselves.

       CMake 2.8.12 and lower  allowed  a  build  target  to  link  to  itself
       directly with a target_link_libraries() call. This is an indicator of a
       bug in user code.

       The OLD behavior for this policy is to ignore targets which list  them-
       selves  in  their  own  link implementation.  The NEW behavior for this
       policy is to report an error if a target attempts to link to itself.

       This policy was introduced in CMake version 3.0.  CMake version  3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0037
       Target  names  should  not be reserved and should match a validity pat-
       tern.

       CMake 2.8.12 and lower allowed creating  targets  using  add_library(),
       add_executable()  and  add_custom_target() with unrestricted choice for
       the target name.  Newer cmake features such as  cmake-generator-expres-
       sions(7) and some diagnostics expect target names to match a restricted
       pattern.

       Target names may contain upper and lower  case  letters,  numbers,  the
       underscore  character  (_), dot(.), plus(+) and minus(-).  As a special
       case, ALIAS and IMPORTED targets may contain two consecutive colons.

       Target names reserved by one or more CMake generators are not  allowed.
       Among others these include all, clean, help, and install.

       Target  names associated with optional features, such as test and pack-
       age, may also be reserved.  CMake 3.10 and below always  reserve  them.
       CMake  3.11  and above reserve them only when the corresponding feature
       is enabled (e.g. by including the CTest or CPack modules).

       The OLD behavior for this policy is  to  allow  creating  targets  with
       reserved  names  or  which  do not match the validity pattern.  The NEW
       behavior for this policy is to report an error if an add_*  command  is
       used with an invalid target name.

       This  policy was introduced in CMake version 3.0.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0036
       The build_name() command should not be called.

       This command was added in May 2001 to compute a name  for  the  current
       operating  system  and compiler combination.  The command has long been
       documented  as  discouraged  and  replaced  by  the  CMAKE_SYSTEM   and
       CMAKE_<LANG>_COMPILER variables.

       CMake  >= 3.0 prefer that this command never be called.  The OLD behav-
       ior for this policy is to allow the command  to  be  called.   The  NEW
       behavior  for this policy is to issue a FATAL_ERROR when the command is
       called.

       This policy was introduced in CMake version 3.0.  CMake version  3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0035
       The variable_requires() command should not be called.

       This  command  was  introduced  in November 2001 to perform some condi-
       tional logic.  It has long been replaced by the if() command.

       CMake >= 3.0 prefer that this command never be called.  The OLD  behav-
       ior  for  this  policy  is  to allow the command to be called.  The NEW
       behavior for this policy is to issue a FATAL_ERROR when the command  is
       called.

       This  policy was introduced in CMake version 3.0.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0034
       The utility_source() command should not be called.

       This command was introduced in March 2001  to  help  build  executables
       used  to generate other files.  This approach has long been replaced by
       add_executable() combined with add_custom_command().

       CMake >= 3.0 prefer that this command never be called.  The OLD  behav-
       ior  for  this  policy  is  to allow the command to be called.  The NEW
       behavior for this policy is to issue a FATAL_ERROR when the command  is
       called.

       This  policy was introduced in CMake version 3.0.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0033
       The export_library_dependencies() command should not be called.

       This command was added in  January  2003  to  export  <tgt>_LIB_DEPENDS
       internal CMake cache entries to a file for installation with a project.
       This was used at the time to allow transitive link dependencies to work
       for  applications outside of the original build tree of a project.  The
       functionality has been superseded by the export()  and  install(EXPORT)
       commands.

       CMake  >= 3.0 prefer that this command never be called.  The OLD behav-
       ior for this policy is to allow the command  to  be  called.   The  NEW
       behavior  for this policy is to issue a FATAL_ERROR when the command is
       called.

       This policy was introduced in CMake version 3.0.  CMake version  3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0032
       The output_required_files() command should not be called.

       This  command  was  added in June 2001 to expose the then-current CMake
       implicit dependency scanner.  CMake's real implicit dependency  scanner
       has  evolved  since  then but is not exposed through this command.  The
       scanning capabilities of this command are very limited and  this  func-
       tionality is better achieved through dedicated outside tools.

       CMake  >= 3.0 prefer that this command never be called.  The OLD behav-
       ior for this policy is to allow the command  to  be  called.   The  NEW
       behavior  for this policy is to issue a FATAL_ERROR when the command is
       called.

       This policy was introduced in CMake version 3.0.  CMake version  3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0031
       The load_command() command should not be called.

       This  command  was  added in August 2002 to allow projects to add arbi-
       trary commands implemented in C or C++.  However, it does not work when
       the  toolchain  in use does not match the ABI of the CMake process.  It
       has been mostly superseded by the macro() and function() commands.

       CMake >= 3.0 prefer that this command never be called.  The OLD  behav-
       ior  for  this  policy  is  to allow the command to be called.  The NEW
       behavior for this policy is to issue a FATAL_ERROR when the command  is
       called.

       This  policy was introduced in CMake version 3.0.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0030
       The use_mangled_mesa() command should not be called.

       This command was created in September 2001 to support VTK before modern
       CMake language and custom command capabilities.  VTK has not used it in
       years.

       CMake >= 3.0 prefer that this command never be called.  The OLD  behav-
       ior  for  this  policy  is  to allow the command to be called.  The NEW
       behavior for this policy is to issue a FATAL_ERROR when the command  is
       called.

       This  policy was introduced in CMake version 3.0.  CMake version 3.21.0
       warns when the policy is not  set  and  uses  OLD  behavior.   Use  the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0029
       The subdir_depends() command should not be called.

       The implementation of this command has been empty since  December  2001
       but was kept in CMake for compatibility for a long time.

       CMake  >= 3.0 prefer that this command never be called.  The OLD behav-
       ior for this policy is to allow the command  to  be  called.   The  NEW
       behavior  for this policy is to issue a FATAL_ERROR when the command is
       called.

       This policy was introduced in CMake version 3.0.  CMake version  3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0028
       Double colon in target name means ALIAS or IMPORTED target.

       CMake 2.8.12 and lower allowed the use of targets and files with double
       colons in target_link_libraries(), with some buildsystem generators.

       The use of double-colons is a common pattern used to namespace IMPORTED
       targets  and  ALIAS targets.  When computing the link dependencies of a
       target, the name of each dependency could either be a target, or a file
       on  disk.   Previously, if a target was not found with a matching name,
       the name was considered to refer to a file on disk.  This can  lead  to
       confusing  error messages if there is a typo in what should be a target
       name.

       The OLD behavior for this policy is to search for targets,  then  files
       on  disk,  even  if  the  search  term contains double-colons.  The NEW
       behavior for this policy is to issue a FATAL_ERROR if a link dependency
       contains  double-colons  but is not an IMPORTED target or an ALIAS tar-
       get.

       This policy was introduced in CMake version 3.0.  CMake version  3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0027
       Conditionally linked imported targets with missing include directories.

       CMake    2.8.11   introduced   introduced   the   concept   of   INTER-
       FACE_INCLUDE_DIRECTORIES, and a check at cmake time that the entries in
       the INTERFACE_INCLUDE_DIRECTORIES of an IMPORTED target actually exist.
       CMake 2.8.11 also introduced generator expression support in  the  tar-
       get_link_libraries() command.  However, if an imported target is linked
       as a result of a generator expression evaluation, the  entries  in  the
       INTERFACE_INCLUDE_DIRECTORIES of that target were not checked for exis-
       tence as they should be.

       The OLD behavior of this policy is to report a warning if an  entry  in
       the  INTERFACE_INCLUDE_DIRECTORIES of a generator-expression condition-
       ally linked IMPORTED target does not exist.

       The NEW behavior of this policy is to report an error if  an  entry  in
       the  INTERFACE_INCLUDE_DIRECTORIES of a generator-expression condition-
       ally linked IMPORTED target does not exist.

       This policy was introduced in CMake version 3.0.  CMake version  3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0026
       Disallow use of the LOCATION property for build targets.

       CMake  2.8.12  and  lower  allowed reading the LOCATION target property
       (and configuration-specific variants) to determine the  eventual  loca-
       tion  of  build targets.  This relies on the assumption that all neces-
       sary information is available at configure-time to determine the  final
       location  and  filename  of  the target.  However, this property is not
       fully determined until later at generate-time.  At generate  time,  the
       $<TARGET_FILE>  generator expression can be used to determine the even-
       tual LOCATION of a target output.

       Code which reads the LOCATION target property can be ported to use  the
       $<TARGET_FILE>  generator  expression  together with the file(GENERATE)
       subcommand to generate a file containing the target location.

       The OLD behavior for this policy is to allow reading the LOCATION prop-
       erties  from build-targets.  The NEW behavior for this policy is to not
       to allow reading the LOCATION properties from build-targets.

       This policy was introduced in CMake version 3.0.  CMake version  3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0025
       Compiler id for Apple Clang is now AppleClang.

       CMake  3.0 and above recognize that Apple Clang is a different compiler
       than upstream Clang and  that  they  have  different  version  numbers.
       CMake   now  prefers  to  present  this  to  projects  by  setting  the
       CMAKE_<LANG>_COMPILER_ID variable to AppleClang instead of Clang.  How-
       ever,  existing  projects may assume the compiler id for Apple Clang is
       just Clang as it was in CMake versions prior to  3.0.   Therefore  this
       policy  determines  for  Apple Clang which compiler id to report in the
       CMAKE_<LANG>_COMPILER_ID variable after language <LANG> is  enabled  by
       the  project()  or  enable_language()  command.  The policy must be set
       prior to the invocation of either command.

       The OLD behavior for this policy is to use compiler id Clang.  The  NEW
       behavior for this policy is to use compiler id AppleClang.

       This  policy  was  introduced in CMake version 3.0.  Use the cmake_pol-
       icy() command to set this policy to OLD or NEW explicitly.  Unlike most
       policies,  CMake version 3.21.0 does not warn by default when this pol-
       icy is not set and simply uses OLD behavior.  See documentation of  the
       CMAKE_POLICY_WARNING_CMP0025 variable to control the warning.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0024
       Disallow include export result.

       CMake 2.8.12 and lower allowed use of the include()  command  with  the
       result of the export() command.  This relies on the assumption that the
       export() command has an immediate effect  at  configure-time  during  a
       cmake  run.   Certain  properties  of  targets are not fully determined
       until later at generate-time, such as the link  language  and  complete
       list  of  link libraries.  Future refactoring will change the effect of
       the export() command to be executed at generate-time.  Use  ALIAS  tar-
       gets  instead in cases where the goal is to refer to targets by another
       name.

       The OLD behavior for this policy is to allow including the result of an
       export()  command.   The  NEW  behavior for this policy is not to allow
       including the result of an export() command.

       This policy was introduced in CMake version 3.0.  CMake version  3.21.0
       warns  when  the  policy  is  not  set  and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 2.8
   CMP0023
       Plain and keyword target_link_libraries() signatures cannot be mixed.

       CMake 2.8.12 introduced the target_link_libraries() signature using the
       PUBLIC, PRIVATE, and INTERFACE keywords to generalize  the  LINK_PUBLIC
       and LINK_PRIVATE keywords introduced in CMake 2.8.7.  Use of signatures
       with any of these keywords sets the link interface of a target  explic-
       itly,  even  if  empty.   This produces confusing behavior when used in
       combination  with  the  historical   behavior   of   the   plain   tar-
       get_link_libraries() signature.  For example, consider the code:

          target_link_libraries(mylib A)
          target_link_libraries(mylib PRIVATE B)

       After  the first line the link interface has not been set explicitly so
       CMake would use the link implementation,  A,  as  the  link  interface.
       However, the second line sets the link interface to empty.  In order to
       avoid this subtle behavior CMake now prefers  to  disallow  mixing  the
       plain  and  keyword  signatures of target_link_libraries() for a single
       target.

       The OLD behavior for this policy is to allow  keyword  and  plain  tar-
       get_link_libraries() signatures to be mixed.  The NEW behavior for this
       policy is to not to allow mixing of the keyword and plain signatures.

       This policy was introduced in  CMake  version  2.8.12.   CMake  version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0022
       INTERFACE_LINK_LIBRARIES defines the link interface.

       CMake  2.8.11 constructed the 'link interface' of a target from proper-
       ties  matching  (IMPORTED_)?LINK_INTERFACE_LIBRARIES(_<CONFIG>)?.   The
       modern  way  to  specify  config-sensitive  content is to use generator
       expressions and the IMPORTED_ prefix makes uniform  processing  of  the
       link  interface  with  generator  expressions  impossible.   The INTER-
       FACE_LINK_LIBRARIES target property was introduced as a replacement  in
       CMake  2.8.12.  This new property is named consistently with the INTER-
       FACE_COMPILE_DEFINITIONS,  INTERFACE_INCLUDE_DIRECTORIES   and   INTER-
       FACE_COMPILE_OPTIONS  properties.  For in-build targets, CMake will use
       the INTERFACE_LINK_LIBRARIES property as the source of the link  inter-
       face  only if policy CMP0022 is NEW.  When exporting a target which has
       this policy set to NEW, only the INTERFACE_LINK_LIBRARIES property will
       be  processed  and generated for the IMPORTED target by default.  A new
       option to the install(EXPORT) and export commands allows export of  the
       old-style  properties  for compatibility with downstream users of CMake
       versions older than 2.8.12.  The target_link_libraries()  command  will
       no    longer    populate    the    properties    matching   LINK_INTER-
       FACE_LIBRARIES(_<CONFIG>)? if this policy is NEW.

       Warning-free  future-compatible  code  which  works  with  CMake  2.8.7
       onwards  can  be written by using the LINK_PRIVATE and LINK_PUBLIC key-
       words of target_link_libraries().

       The  OLD  behavior  for  this  policy   is   to   ignore   the   INTER-
       FACE_LINK_LIBRARIES  property  for  in-build targets.  The NEW behavior
       for this policy is to use  the  INTERFACE_LINK_LIBRARIES  property  for
       in-build    targets,   and   ignore   the   old   properties   matching
       (IMPORTED_)?LINK_INTERFACE_LIBRARIES(_<CONFIG>)?.

       This policy was introduced in  CMake  version  2.8.12.   CMake  version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0021
       Fatal error on relative paths in INCLUDE_DIRECTORIES target property.

       CMake  2.8.10.2  and lower allowed the INCLUDE_DIRECTORIES target prop-
       erty to contain relative  paths.   The  base  path  for  such  relative
       entries  is not well defined.  CMake 2.8.12 issues a FATAL_ERROR if the
       INCLUDE_DIRECTORIES property contains a relative path.

       The OLD behavior for this policy is not to warn about relative paths in
       the  INCLUDE_DIRECTORIES  target  property.   The NEW behavior for this
       policy is to issue a FATAL_ERROR if INCLUDE_DIRECTORIES contains a rel-
       ative path.

       This  policy  was  introduced  in  CMake version 2.8.12.  CMake version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0020
       Automatically link Qt executables to qtmain target on Windows.

       CMake 2.8.10 and lower required users of Qt to always  specify  a  link
       dependency to the qtmain.lib static library manually on Windows.  CMake
       2.8.11 gained the  ability  to  evaluate  generator  expressions  while
       determining  the  link dependencies from IMPORTED targets.  This allows
       CMake itself to automatically link executables which link to Qt to  the
       qtmain.lib  library  when  using IMPORTED Qt targets.  For applications
       already linking to qtmain.lib, this should  have  little  impact.   For
       applications  which supply their own alternative WinMain implementation
       and for applications which use the QAxServer  library,  this  automatic
       linking will need to be disabled as per the documentation.

       The  OLD  behavior  for  this  policy  is  not  to  link executables to
       qtmain.lib automatically when they link to the QtCore IMPORTED  target.
       The  NEW  behavior for this policy is to link executables to qtmain.lib
       automatically when they link to QtCore IMPORTED target.

       This policy was introduced in  CMake  version  2.8.11.   CMake  version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0019
       Do not re-expand variables in include and link information.

       CMake  2.8.10 and lower re-evaluated values given to the include_direc-
       tories, link_directories, and link_libraries  commands  to  expand  any
       leftover  variable  references  at  the  end of the configuration step.
       This was for  strict  compatibility  with  VERY  early  CMake  versions
       because all variable references are now normally evaluated during CMake
       language processing.  CMake 2.8.11 and higher prefer to skip the  extra
       evaluation.

       The  OLD  behavior  for  this  policy  is to re-evaluate the values for
       strict compatibility.  The NEW behavior for this policy is to leave the
       values untouched.

       This  policy  was  introduced  in  CMake version 2.8.11.  CMake version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0018
       Ignore CMAKE_SHARED_LIBRARY_<Lang>_FLAGS variable.

       CMake 2.8.8 and lower compiled sources in SHARED and  MODULE  libraries
       using  the  value of the undocumented CMAKE_SHARED_LIBRARY_<Lang>_FLAGS
       platform variable.   The  variable  contained  platform-specific  flags
       needed  to compile objects for shared libraries.  Typically it included
       a flag such as -fPIC for position independent code  but  also  included
       other flags needed on certain platforms.  CMake 2.8.9 and higher prefer
       instead to use the POSITION_INDEPENDENT_CODE target property to  deter-
       mine  what targets should be position independent, and new undocumented
       platform    variables    to     select     flags     while     ignoring
       CMAKE_SHARED_LIBRARY_<Lang>_FLAGS completely.

       The  default  for either approach produces identical compilation flags,
       but if a project modifies  CMAKE_SHARED_LIBRARY_<Lang>_FLAGS  from  its
       original value this policy determines which approach to use.

       The  OLD  behavior  for  this policy is to ignore the POSITION_INDEPEN-
       DENT_CODE property for all  targets  and  use  the  modified  value  of
       CMAKE_SHARED_LIBRARY_<Lang>_FLAGS for SHARED and MODULE libraries.

       The     NEW     behavior    for    this    policy    is    to    ignore
       CMAKE_SHARED_LIBRARY_<Lang>_FLAGS whether it is  modified  or  not  and
       honor the POSITION_INDEPENDENT_CODE target property.

       This  policy  was  introduced  in  CMake  version 2.8.9.  CMake version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0017
       Prefer files from the CMake module directory when including from there.

       Starting with CMake 2.8.4, if a cmake-module shipped with  CMake  (i.e.
       located  in  the  CMake module directory) calls include() or find_pack-
       age(), the files located in the CMake module  directory  are  preferred
       over  the files in CMAKE_MODULE_PATH.  This makes sure that the modules
       belonging to CMake always get those files included which  they  expect,
       and  against which they were developed and tested.  In all other cases,
       the files found in CMAKE_MODULE_PATH still  take  precedence  over  the
       ones in the CMake module directory.  The OLD behavior is to always pre-
       fer files from CMAKE_MODULE_PATH over  files  from  the  CMake  modules
       directory.

       This  policy  was  introduced  in  CMake  version 2.8.4.  CMake version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0016
       target_link_libraries() reports error if its only  argument  is  not  a
       target.

       In  CMake  2.8.2 and lower the target_link_libraries() command silently
       ignored if it was called with only  one  argument,  and  this  argument
       wasn't a valid target.  In CMake 2.8.3 and above it reports an error in
       this case.

       This policy was introduced  in  CMake  version  2.8.3.   CMake  version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0015
          link_directories() treats paths relative to the source dir.

       In CMake 2.8.0 and lower the link_directories() command passed relative
       paths  unchanged  to  the  linker.   In  CMake  2.8.1  and  above   the
       link_directories()  command  prefers  to  interpret relative paths with
       respect  to  CMAKE_CURRENT_SOURCE_DIR,   which   is   consistent   with
       include_directories()  and  other  commands.  The OLD behavior for this
       policy is to use relative paths verbatim in the  linker  command.   The
       NEW  behavior  for this policy is to convert relative paths to absolute
       paths by appending the relative path to CMAKE_CURRENT_SOURCE_DIR.

       This policy was introduced  in  CMake  version  2.8.1.   CMake  version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0014
       Input directories must have CMakeLists.txt.

       CMake versions before 2.8 silently ignored missing CMakeLists.txt files
       in directories referenced by add_subdirectory() or  subdirs(), treating
       them as if present but empty.  In CMake 2.8.0 and above this cmake_pol-
       icy() determines whether or not the case is an error.  The OLD behavior
       for  this  policy  is to silently ignore the problem.  The NEW behavior
       for this policy is to report an error.

       This policy was introduced  in  CMake  version  2.8.0.   CMake  version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0013
       Duplicate binary directories are not allowed.

       CMake  2.6.3  and  below silently permitted add_subdirectory() calls to
       create the same binary directory multiple times.  During  build  system
       generation  files  would  be  written and then overwritten in the build
       tree and could lead to strange behavior.  CMake 2.6.4 and above explic-
       itly detect duplicate binary directories.  CMake 2.6.4 always considers
       this case an error.  In CMake 2.8.0 and above  this  policy  determines
       whether  or not the case is an error.  The OLD behavior for this policy
       is to allow duplicate binary directories.  The NEW  behavior  for  this
       policy is to disallow duplicate binary directories with an error.

       This  policy  was  introduced  in  CMake  version 2.8.0.  CMake version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0012
       if() recognizes numbers and boolean constants.

       In CMake versions 2.6.4 and lower the if() command implicitly  derefer-
       enced  arguments corresponding to variables, even those named like num-
       bers or boolean constants, except for 0 and  1.   Numbers  and  boolean
       constants such as true, false, yes, no, on, off, y, n, notfound, ignore
       (all case insensitive) were recognized in some cases but not all.   For
       example, the code if(TRUE) might have evaluated as false.  Numbers such
       as 2 were recognized only in boolean expressions like if(NOT 2)  (lead-
       ing  to false) but not as a single-argument like if(2) (also leading to
       false).  Later versions of CMake prefer to treat  numbers  and  boolean
       constants literally, so they should not be used as variable names.

       The OLD behavior for this policy is to implicitly dereference variables
       named like numbers and boolean constants.  The NEW  behavior  for  this
       policy  is  to recognize numbers and boolean constants without derefer-
       encing variables with such names.

       This policy was introduced  in  CMake  version  2.8.0.   CMake  version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

POLICIES INTRODUCED BY CMAKE 2.6
   CMP0011
       Included scripts do automatic cmake_policy() PUSH and POP.

       In  CMake  2.6.2  and below, CMake Policy settings in scripts loaded by
       the include() and find_package() commands would  affect  the  includer.
       Explicit  invocations  of cmake_policy(PUSH) and cmake_policy(POP) were
       required to isolate policy changes and  protect  the  includer.   While
       some  scripts  intend to affect the policies of their includer, most do
       not.  In CMake 2.6.3 and above, include() and find_package() by default
       PUSH  and  POP  an entry on the policy stack around an included script,
       but provide a NO_POLICY_SCOPE option to disable it.  This policy deter-
       mines  whether  or not to imply NO_POLICY_SCOPE for compatibility.  The
       OLD behavior for this policy is to imply NO_POLICY_SCOPE for  include()
       and  find_package()  commands.   The NEW behavior for this policy is to
       allow the commands to do their default cmake_policy PUSH and POP.

       This policy was introduced  in  CMake  version  2.6.3.   CMake  version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0010
       Bad variable reference syntax is an error.

       In CMake 2.6.2 and below, incorrect variable reference syntax such as a
       missing close-brace (${FOO) was reported but did not stop processing of
       CMake code.  This policy determines whether a bad variable reference is
       an error.  The OLD behavior for this policy is to warn about the error,
       leave  the  string  untouched, and continue.  The NEW behavior for this
       policy is to report an error.

       If CMP0053 is set to NEW, this policy has no effect and is  treated  as
       always being NEW.

       This  policy  was  introduced  in  CMake  version 2.6.3.  CMake version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0009
       FILE GLOB_RECURSE calls should not follow symlinks by default.

       In CMake 2.6.1 and below, file(GLOB_RECURSE) calls would follow through
       symlinks,  sometimes  coming  up  with  unexpectedly  large result sets
       because of symlinks to top level directories that contain  hundreds  of
       thousands of files.

       This  policy  determines  whether or not to follow symlinks encountered
       during a file(GLOB_RECURSE) call.  The OLD behavior for this policy  is
       to  follow  the  symlinks.   The NEW behavior for this policy is not to
       follow the symlinks by default, but only if FOLLOW_SYMLINKS is given as
       an additional argument to the FILE command.

       This  policy  was  introduced  in  CMake  version 2.6.2.  CMake version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0008
       Libraries linked by full-path must have a valid library file name.

       In CMake 2.4 and below it is possible to write code like

          target_link_libraries(myexe /full/path/to/somelib)

       where somelib is supposed to be a valid library file name such as  lib-
       somelib.a  or  somelib.lib.   For  Makefile generators this produces an
       error at build time because the dependency on the full path  cannot  be
       found.  For Visual Studio Generators IDE and Xcode generators this used
       to work by accident because CMake would always split  off  the  library
       directory  and  ask  the  linker  to  search  for  the  library by name
       (-lsomelib or somelib.lib).  Despite the failure with  Makefiles,  some
       projects  have  code like this and build only with Visual Studio and/or
       Xcode.  This version of CMake prefers to pass the full path directly to
       the native build tool, which will fail in this case because it does not
       name a valid library file.

       This policy determines what to do with full paths that do not appear to
       name  a  valid  library  file.   The OLD behavior for this policy is to
       split the library name from the path and ask the linker to  search  for
       it.   The  NEW  behavior for this policy is to trust the given path and
       pass it directly to the native build tool unchanged.

       This policy was introduced  in  CMake  version  2.6.1.   CMake  version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0007
       list command no longer ignores empty elements.

       This  policy determines whether the list command will ignore empty ele-
       ments in the list.  CMake 2.4 and below list commands ignored all empty
       elements  in the list.  For example, a;b;;c would have length 3 and not
       4.  The OLD behavior for this policy is to ignore empty list  elements.
       The  NEW  behavior for this policy is to correctly count empty elements
       in a list.

       This policy was introduced  in  CMake  version  2.6.0.   CMake  version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0006
       Installing MACOSX_BUNDLE targets requires a BUNDLE DESTINATION.

       This  policy  determines  whether  the install(TARGETS) command must be
       given a BUNDLE DESTINATION when asked to  install  a  target  with  the
       MACOSX_BUNDLE  property  set.   CMake 2.4 and below did not distinguish
       application bundles from normal executables  when  installing  targets.
       CMake 2.6 provides a BUNDLE option to the install(TARGETS) command that
       specifies rules specific to application bundles on the  Mac.   Projects
       should  use this option when installing a target with the MACOSX_BUNDLE
       property set.

       The OLD behavior for this policy is to fall back to the RUNTIME  DESTI-
       NATION if a BUNDLE DESTINATION is not given.  The NEW behavior for this
       policy is to produce an error if a bundle target is installed without a
       BUNDLE DESTINATION.

       This  policy  was  introduced  in  CMake  version 2.6.0.  CMake version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0005
       Preprocessor definition values are now escaped automatically.

       This policy determines whether or not  CMake  should  generate  escaped
       preprocessor  definition  values added via add_definitions.  CMake ver-
       sions 2.4 and below assumed that only trivial values would be given for
       macros  in  add_definitions  calls.   It  did  not  attempt  to  escape
       non-trivial values such as string literals in  generated  build  rules.
       CMake  versions 2.6 and above support escaping of most values, but can-
       not assume the user has not added escapes already in an attempt to work
       around limitations in earlier versions.

       The OLD behavior for this policy is to place definition values given to
       add_definitions directly in the generated build rules without  attempt-
       ing  to escape anything.  The NEW behavior for this policy is to gener-
       ate correct escapes for all native build tools automatically.  See doc-
       umentation  of  the COMPILE_DEFINITIONS target property for limitations
       of the escaping implementation.

       This policy was introduced  in  CMake  version  2.6.0.   CMake  version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0004
       Libraries linked may not have leading or trailing whitespace.

       CMake  versions  2.4  and  below  silently removed leading and trailing
       whitespace from libraries linked with code like

          target_link_libraries(myexe " A ")

       This could lead to subtle errors in user projects.

       The OLD behavior for this policy is  to  silently  remove  leading  and
       trailing  whitespace.   The NEW behavior for this policy is to diagnose
       the existence of such whitespace as an error.   The  setting  for  this
       policy  used when checking the library names is that in effect when the
       target is created by an add_executable() or add_library() command.

       This policy was introduced  in  CMake  version  2.6.0.   CMake  version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0003
       Libraries linked via full path no longer produce linker search paths.

       This  policy  affects  how libraries whose full paths are NOT known are
       found at link time, but was created due to a change in how CMake  deals
       with libraries whose full paths are known.  Consider the code

          target_link_libraries(myexe /path/to/libA.so)

       CMake  2.4  and below implemented linking to libraries whose full paths
       are known by splitting them on the link line into  separate  components
       consisting of the linker search path and the library name.  The example
       code might have produced something like

          ... -L/path/to -lA ...

       in order to link to library A.  An analysis was performed to order mul-
       tiple link directories such that the linker would find library A in the
       desired location, but there are cases in  which  this  does  not  work.
       CMake  versions 2.6 and above use the more reliable approach of passing
       the full path to libraries directly to the linker in most  cases.   The
       example code now produces something like

          ... /path/to/libA.so ....

       Unfortunately this change can break code like

          target_link_libraries(myexe /path/to/libA.so B)

       where  B is meant to find /path/to/libB.so.  This code is wrong because
       the user is asking the linker to find library B but has not provided  a
       linker  search  path (which may be added with the link_directories com-
       mand).  However, with the old linking  implementation  the  code  would
       work  accidentally  because  the linker search path added for library A
       allowed library B to be found.

       In order to support projects depending on linker search paths added  by
       linking  to  libraries with known full paths, the OLD behavior for this
       policy will add the linker search paths even though they are not needed
       for  their  own  libraries.  When this policy is set to OLD, CMake will
       produce a link line such as

          ... -L/path/to /path/to/libA.so -lB ...

       which will allow library B to be found as it was previously.  When this
       policy is set to NEW, CMake will produce a link line such as

          ... /path/to/libA.so -lB ...

       which more accurately matches what the project specified.

       The  setting for this policy used when generating the link line is that
       in  effect  when  the  target  is  created  by  an  add_executable   or
       add_library command.  For the example described above, the code

          cmake_policy(SET CMP0003 OLD) # or cmake_policy(VERSION 2.4)
          add_executable(myexe myexe.c)
          target_link_libraries(myexe /path/to/libA.so B)

       will  work  and  suppress  the warning for this policy.  It may also be
       updated to work with the corrected linking approach:

          cmake_policy(SET CMP0003 NEW) # or cmake_policy(VERSION 2.6)
          link_directories(/path/to) # needed to find library B
          add_executable(myexe myexe.c)
          target_link_libraries(myexe /path/to/libA.so B)

       Even better, library B may be specified with a full path:

          add_executable(myexe myexe.c)
          target_link_libraries(myexe /path/to/libA.so /path/to/libB.so)

       When all items on the link line have known paths CMake does  not  check
       this policy so it has no effect.

       Note  that  the  warning for this policy will be issued for at most one
       target.  This avoids flooding users with messages for every target when
       setting the policy once will probably fix all targets.

       This  policy  was  introduced  in  CMake  version 2.6.0.  CMake version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0002
       Logical target names must be globally unique.

       Targets names created with add_executable(), add_library(), or add_cus-
       tom_target() are logical build target names.  Logical target names must
       be globally unique because:

          - Unique names may be referenced unambiguously both in CMake
            code and on make tool command lines.
          - Logical names are used by Xcode and VS IDE generators
            to produce meaningful project names for the targets.

       The logical name of executable and library targets  does  not  have  to
       correspond  to  the physical file names built.  Consider using the OUT-
       PUT_NAME target property to create two targets with the  same  physical
       name  while keeping logical names distinct.  Custom targets must simply
       have globally  unique  names  (unless  one  uses  the  global  property
       ALLOW_DUPLICATE_CUSTOM_TARGETS with a Makefiles generator).

       This  policy  was  introduced  in  CMake  version 2.6.0.  CMake version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

   CMP0001
       CMAKE_BACKWARDS_COMPATIBILITY should no longer be used.

       The behavior is to check CMAKE_BACKWARDS_COMPATIBILITY and  present  it
       to the user.  The NEW behavior is to ignore CMAKE_BACKWARDS_COMPATIBIL-
       ITY completely.

       In CMake 2.4 and below the variable  CMAKE_BACKWARDS_COMPATIBILITY  was
       used to request compatibility with earlier versions of CMake.  In CMake
       2.6 and above all compatibility issues are handled by policies and  the
       cmake_policy()  command.   However,  CMake must still check CMAKE_BACK-
       WARDS_COMPATIBILITY for projects written for CMake 2.4 and below.

       This policy was introduced  in  CMake  version  2.6.0.   CMake  version
       3.21.0 warns when the policy is not set and uses OLD behavior.  Use the
       cmake_policy() command to set it to OLD or NEW explicitly.

       NOTE:
          The OLD behavior of a policy is deprecated by definition and may  be
          removed in a future version of CMake.

   CMP0000
       A minimum required CMake version must be specified.

       CMake requires that projects specify the version of CMake to which they
       have been written.  This policy has been put in place so  users  trying
       to  build the project may be told when they need to update their CMake.
       Specifying a version also helps the project build with  CMake  versions
       newer than that specified.  Use the cmake_minimum_required() command at
       the top of your main CMakeLists.txt file:

          cmake_minimum_required(VERSION <major>.<minor>)

       where <major>.<minor> is the version of CMake you want to support (such
       as  3.14).   The command will ensure that at least the given version of
       CMake is running  and  help  newer  versions  be  compatible  with  the
       project.  See documentation of cmake_minimum_required() for details.

       Note that the command invocation must appear in the CMakeLists.txt file
       itself; a call in an included file is  not  sufficient.   However,  the
       cmake_policy()  command  may  be called to set policy CMP0000 to OLD or
       NEW behavior explicitly.  The OLD behavior is to  silently  ignore  the
       missing invocation.  The NEW behavior is to issue an error instead of a
       warning.  An included file may set CMP0000  explicitly  to  affect  how
       this policy is enforced for the main CMakeLists.txt file.

       This policy was introduced in CMake version 2.6.0.

       NOTE:
          The  OLD behavior of a policy is deprecated by definition and may be
          removed in a future version of CMake.

COPYRIGHT
       2000-2021 Kitware, Inc. and Contributors



ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+-----------------------+
       |ATTRIBUTE TYPE |   ATTRIBUTE VALUE     |
       +---------------+-----------------------+
       |Availability   | developer/build/cmake |
       +---------------+-----------------------+
       |Stability      | Uncommitted           |
       +---------------+-----------------------+

NOTES
       Source code for open source software components in Oracle  Solaris  can
       be found at https://www.oracle.com/downloads/opensource/solaris-source-
       code-downloads.html.

       This    software    was    built    from    source     available     at
       https://github.com/oracle/solaris-userland.    The  original  community
       source                was                downloaded                from
       http://www.cmake.org/files/v3.21/cmake-3.21.0.tar.gz.

       Further information about this software can be found on the open source
       community website at http://www.cmake.org/.



3.21.0                           Dec 22, 2021                CMAKE-POLICIES(7)