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Oracle Solaris Studio 12.3: C++ User's Guide Oracle Solaris Studio 12.3 Information Library |
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Oracle Solaris Studio 12.3: C++ User's Guide Oracle Solaris Studio 12.3 Information Library |
3. Using the C++ Compiler Options
6. Creating and Using Templates
9. Improving Program Performance
10. Building Multithreaded Programs
12. Using the C++ Standard Library
13. Using the Classic iostream Library
A.1 How Option Information Is Organized
A.2.18 -filt[=filter[,filter...]]
A.2.75 -Qoption phase option[,option...]
A.2.80 -Rpathname[:pathname...]
A.2.88 -traceback[={%none|common|signals_list}]
A.2.101.2 -xalias_level=simple
A.2.101.3 -xalias_level=compatible
A.2.105.1 -xarch Flags for SPARC and x86
A.2.105.2 -xarch Flags for SPARC
A.2.105.3 -xarch Flags for x86
A.2.107 -xbinopt={prepare|off}
A.2.108 -xbuiltin[={%all|%default|%none}]
A.2.114 -xdebugformat=[stabs|dwarf]
A.2.116 -xdumpmacros[=value[,value...]]
A.2.122 -xinline[=func-spec[,func-spec...]]
A.2.123 -xinstrument=[no%]datarace
A.2.124.4 When Not To Use -xipo Interprocedural Analysis
A.2.128 -xkeepframe[=[%all,%none,name,no%name]]
A.2.129 -xlang=language[,language]
A.2.156.1 Creating a Precompiled-Header File
A.2.162 -xprefetch_auto_type=a
A.2.165 -xprofile_ircache[=path]
A.2.173.1 --xtarget Values By Platform
A.2.176 -xtrigraphs[={yes|no}]
The following section alphabetically lists all the C++ compiler options and indicates any platform restrictions.
Turns on verbose mode, showing how command options expand. Shows each component as it is invoked.
Shows each component as it would be invoked, but does not actually execute it. Also shows how command options would expand.
Specifies whether a library binding for linking is symbolic, dynamic (shared), or static (nonshared).
You can use the –B option several times on a command line. This option is passed to the linker, ld.
Note - Many system libraries are only available as dynamic libraries in the Oracle Solaris 64-bit compilation environment. Therefore, do not use -Bstatic as the last toggle on the command line.
binding must be one of the values listed in the following table:
|
(No space is allowed between –B and the binding value.)
If -B is not specified, –Bdynamic is assumed.
To link the C++ default libraries statically, use the –staticlib option.
The -Bstatic and -Bdynamic options affect the linking of the libraries that are provided by default. To ensure that the default libraries are linked dynamically, the last use of –B should be –Bdynamic.
In a 64-bit environment, many system libraries are available only as shared dynamic libraries. These include libm.so and libc.so (libm.a and libc.a are not provided). As a result, -Bstatic and -dn may cause linking errors in 64-bit Oracle Solaris operating system environments. Applications must link with the dynamic libraries in these cases.
The following compiler command links libfoo.a even if libfoo.so exists; all other libraries are linked dynamically:
example% CC a.o –Bstatic –lfoo –Bdynamic
Never use -Bsymbolic with programs containing C++ code, use linker map files instead.
With -Bsymbolic, references in different modules can bind to different copies of what is supposed to be one global object.
The exception mechanism relies on comparing addresses. If you have two copies of something, their addresses won’t compare equal, and the exception mechanism can fail because the exception mechanism relies on comparing what are supposed to be unique addresses.
If you compile and link in separate steps and are using the -Bbinding option, you must include the option in the link step.
–nolib, –staticlib, ld(1) man page, 11.5 Statically Linking Standard Libraries, Linker and Libraries Guide
Compile only; produce object .o files, but suppress linking.
This option directs the CC driver to suppress linking with ld and produce a .o file for each source file. If you specify only one source file on the command line, then you can explicitly name the object file with the -o option.
If you enter CC -c x.cc, the x.o object file is generated.
If you enter CC -c x.cc -o y.o, the y.o object file is generated.
When the compiler produces object code for an input file (.c, .i), the compiler always produces a .o file in the working directory. If you suppress the linking step, the .o files are not removed.
–o filename, –xe
(SPARC) Obsolete, do not use this option. Current Oracle Solaris operating system software no longer supports SPARC V7 architecture. Compiling with this option generates code that runs slower on current SPARC platforms. Use -xO instead and take advantage of compiler defaults for -xarch, -xchip, and -xcache.
Sets the major release compatibility mode of the compiler. This option controls the __SUNPRO_CC_COMPAT preprocessor macro.
The C++ compiler has two principal modes. The default -compat=5 accepts constructs according to the ANSI/ISO 1998 C++ standard as updated in 2003, and generates code compatible with C++ 5.0 through 5.12 in -compat=5 mode. The -compat=g option adds source and binary compatibility with the gcc/g++ compiler on Oracle Solaris x86 and Linux platforms. These modes are incompatible with each other due to significant and incompatible changes in name mangling, class layout, vtable layout, and other ABI details.
Compatibility Mode (-compat=4), which accepted the sematics and language defined by the 4.2 compiler in previous releases, is no longer available.
These modes are differentiated by the –compat option as shown in the following section.
The -compat option can have the values shown in the following table.
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With -compat=g, binary compatibility extends only to shared (dynamic or .so) libraries, not to individual .o files or archive (.a) libraries.
The following example shows linking a g++ shared library to a C++ main program:
% g++ -shared -o libfoo.so -fpic a.cc b.cc c.cc % CC -compat=g main.cc -L. -lfoo
The following example shows linking a C++ shared library to a g++ main program:
% CC -compat=g -G -o libfoo.so -Kpic a.cc b.cc c.cc % g++ main.cc -L. -lfoo
If the –compat option is not specified, –compat=5 is assumed.
See —features for additional information.
When building a shared library, do not use -Bsymbolic.
Does not expand C++ inline functions.
Under the C++ language rules, a C++ inline function is a function for which one of the following statements is true:
The function is defined using the inline keyword,
The function is defined, not just declared, inside a class definition
The function is a compiler-generated class member function
Under the C++ language rules, the compiler can choose whether actually to inline a call to an inline function. The C++ compiler inlines calls to an inline function unless one of the following is true:
The function is too complex
The +d option is selected
The —g option is selected without a —xOn optimization level specified
By default, the compiler may inline the functions f() and memf2() in the following code example. In addition, the class has a default compiler-generated constructor and destructor that the compiler may inline. When you use +d, the compiler will not inline f()and C::mf2(), the constructor, and the destructor.
inline int f() {return 0;} // may be inlined
class C {
int mf1(); // not inlined unless inline definition comes later
int mf2() {return 0;} // may be inlined
};
This option is automatically turned on when you specify –g, the debugging option,, unless an optimization level is also specified (—O or —xO).
The –g0 debugging option does not turn on +d.
The +d option has no effect on the automatic inlining that is performed when you use -xO4 or -xO5.
–g0, –g
Defines the macro symbol name to the preprocessor.
Using this option is equivalent to including a #define directive at the beginning of the source. You can use multiple -D options.
See the CC(1) man page for a list of compiler predefined macros.
Allows or disallows dynamic libraries for the entire executable.
This option is passed to ld.
This option can appear only once on the command line.
|
If no -d option is specified, –dy is assumed.
In a 64-bit environment, many system libraries are available only as shared dynamic libraries. These include libm.so and libc.so (libm.a and libc.a are not provided). As a result, -Bstatic and -dn may cause linking errors in 64-bit Oracle Solaris operating systems. Applications must link with the dynamic libraries in these cases.
This option causes fatal errors if you use it in combination with dynamic libraries. Most system libraries are only available as dynamic libraries.
ld(1) man page, Linker and Libraries Guide
(SPARC) Obsolete — Do not use. Use -xmemalign=8s. See A.2.145 -xmemalign=ab for more information.
This option is silently ignored on x86 platforms.
Shows the subcommands built by driver, but does not compile.
This option directs the CC driver to show, but not execute, the subcommands constructed by the compilation driver.
Runs the preprocessor on source files; does not compile.
Directs the CC driver to run only the preprocessor on C++ source files, and to send the result to stdout (standard output). No compilation is done; no .o files are generated.
This option causes preprocessor-type line number information to be included in the output.
To compile the output of the -E option when the source code involves templates, you might need to use the -template=no%extdef option with the -E option. If application code uses the definitions separate template source code model, the output of the -E option might still not compile. Refer to the chapters on templates for more information.
This option is useful for determining the changes made by the preprocessor. For example, the following program, foo.cc, generates the output shown in A.2.12.1 Examples
Example A-1 Preprocessor Example Program foo.cc
#if __cplusplus < 199711L
int power(int, int);
#else
template <> int power(int, int);
#endif
int main () {
int x;
x=power(2, 10);
}
.Example A-2 Preprocessor Output of foo.cc Using -E Option
example% CC -E foo.cc
#4 "foo.cc"
template < > int power (int, int);
int main () {
int x;
x = power (2, 10);
}
The output of this option might not be usable as input to a C++ compilation if the code contains templates under the definitions-separate model.
–P
This command suppresses C++ compiler warning messages and has no effect on error messages. This option applies to all warning messages regardless of whether they have been designated by -errwarn to cause a non-zero exit status.
t is a comma-separated list that consists of one or more of the following: tag, no%tag, %all, %none. Order is important; for example, %all,no%tag suppresses all warning messages except tag. The following table lists the -erroff values.
Table A-2 -erroff Values
|
The default is -erroff=%none. Specifying -erroff is equivalent to specifying -erroff=%all.
For example, -erroff=tag suppresses the warning message specified by this tag. On the other hand, -erroff=%all,no%tag suppresses all warning messages except the messages identified by tag.
You can display the tag for a warning message by using the -errtags=yes option.
Only warning messages from the C++ compiler front-end that display a tag when the -errtags option is used can be suppressed with the -erroff option.
-errtags, -errwarn
Displays the message tag for each warning message of the C++ compiler front-end that can be suppressed with the -erroff option or made a fatal warning with the -errwarn option.
a can be either yes or no. The default is -errtags=no. Specifying -errtags is equivalent to specifying -errtags=yes.
Messages from the C++ compiler driver and other components of the compilation system do not have error tags. Therefore they cannot be suppressed with -erroff or made fatal with -errwarn.
-erroff, -errwarn
Use -errwarn to cause the C++ compiler to exit with a failure status for the given warning messages.
t is a comma-separated list that consists of one or more of the following: tag, no%tag, %all, %none. Order is important; for example %all,no%tag causes cc to exit with a fatal status if any warning except tag is issued.
The following table details the -errwarn values.
Table A-3 -errwarn Values
|
The default is -errwarn=%none. Specifying -errwarn alone is equivalent to -errwarn=%all.
Only warning messages from the C++ compiler front-end that display a tag when the -errtags option is used can be specified with the -errwarn option to cause the compiler to exit with a failure status.
The warning messages generated by the C++ compiler change from release to release as the compiler error checking improves and features are added. Code that compiles using -errwarn=%all without error may not compile without error in the next release of the compiler.
-erroff, -errtags, -xwe
This option is a macro that can be effectively used as a starting point for tuning an executable for maximum runtime performance. -fast is a macro that can change from one release of the compiler to the next and expands to options that are target platform specific. Use the -dryrun or -xdryrun option to examine the expansion of -fast, and incorporate the appropriate options of -fast into the ongoing process of tuning the executable.
This option is a macro that selects a combination of compilation options for optimum execution speed on the machine upon which the code is compiled.
This option provides near maximum performance for many applications by expanding to the following compilation options.
Table A-4 -fast Expansion
|
The -fast macro expands into compilation options that may affect other specified options. For example, in the following command, the expansion of the -fast macro includes -xtarget=native which reverts -xarch to one of the 32-bit architecture options.
Incorrect:
example% CC -xarch=sparcvis2 -fast test.cc
Correct:
example% CC -fast -xarch=sparcvis2 test.cc
See the description for each option to determine possible interactions.
The code generation option, the optimization level, the optimization of built-in functions, and the use of inline template files can be overridden by subsequent options (see examples). The optimization level that you specify overrides a previously set optimization level.
The –fast option includes –fns –ftrap=%none; that is, this option turns off all trapping.
On x86 the —fast option includes —xregs=frameptr. See the discussion of this option for details, especially when compiling mixed C, Fortran, and C++ source codes.
The following compiler command results in an optimization level of –xO3.
example% CC –fast –xO3
The following compiler command results in an optimization level of –xO5.
example% CC -xO3 –fast
If you compile and link in separate steps, the -fast option must appear in both the compile command and the link command.
Object binaries compiled with the -fast option are not portable. For example, using the following command on an UltraSPARC III system generates a binary that will not execute on an UltraSPARC II system.
example% CC -fast test.cc
Do not use this option for programs that depend on IEEE standard floating-point arithmetic. Different numerical results, premature program termination, or unexpected SIGFPE signals can occur.
The expansion of -fast includes -D_MATHERR_ERRNO_DONTCARE.
With -fast, the compiler is free to replace calls to floating-point functions with equivalent optimized code that does not set the errno variable. Further, -fast also defines the macro __MATHERR_ERRNO_DONTCARE, which allows the compiler to ignore ensuring the validity of errno and floating-point exceptions raised after a floating-point function call. As a result, user code that relies on the value of errno or an appropriate floating-point exception raised after a floating-point function call could produce inconsistent results.
One way around this problem is to avoid compiling such codes with -fast. However, if -fast optimization is required and the code depends on the value of errno being set properly or a floating-point exception being raised after floating-point library calls, you should compile with the following options after -fast on the command line to inhibit the compiler from optimizing out such library calls:
-xbuiltin=%none -U__MATHERR_ERRNO_DONTCARE -xnolibmopt -xnolibmil
To display the expansion of —fast on any platform, run the command CC —dryrun —fast as shown in the following example.
>CC -dryrun -fast |& grep ### ### command line files and options (expanded): ### -dryrun -xO5 -xarch=sparcvis2 -xcache=64/32/4:1024/64/4 \ -xchip=ultra3i -xmemalign=8s -fsimple=2 -fns=yes -ftrap=%none \ -xlibmil -xlibmopt -xbuiltin=%all -D__MATHERR_ERRNO_DONTCARE
-fns, -fsimple, -ftrap=%none, -xlibmil, -nofstore, -xO5, -xlibmopt, -xtarget=native
Enables/disables various C++ language features named in a comma-separated list.
Keyword a can have the values shown in the following table. The no% prefix disables the associated option.
Table A-5 -features Values
|
This option accumulates instead of overrides.
Use of the following is not compatible with the standard libraries and headers:
no%bool
no%except
no%mutable
Do not use -features=%all or -features=%none. These keywords are deprecated and might be removed in a future release. Results can be unpredictable.
The behavior of a program might change when you use the -features=tmplife option. Testing whether the program works both with and without the -features=tmplife option is one way to test the program’s portability.
Table 3-17 and the C++ Migration Guide
Controls the filtering that the compiler normally applies to linker and compiler error messages.
filter must be one of the values listed in the following table. The %no prefix disables the associated suboption.
Table A-6 -filt Values
|
If you do not specify the -filt option or if you specify -filt without any values, then the compiler assumes -filt=%all.
The following examples show the effects of compiling this code with the -filt option.
// filt_demo.cc
class type {
public:
virtual ~type(); // no definition provided
};
int main()
{
type t;
}
When you compile the code without the -filt option, the compiler assumes -filt=errors,names,returns,stdlib and displays the standard output.
example% CC filt_demo.cc Undefined first referenced symbol in file type::~type() filt_demo.o type::__vtbl filt_demo.o [Hint: try checking whether the first non-inlined, / non-pure virtual function of class type is defined] ld: fatal: Symbol referencing errors. No output written to a.out
The following command suppresses the demangling of the of the C++ mangled linker names and suppresses the C++ explanations of linker errors.
example% CC -filt=no%names,no%errors filt_demo.cc Undefined first referenced symbol in file __1cEtype2T6M_v_ filt_demo.o __1cEtypeG__vtbl_ filt_demo.o ld: fatal: Symbol referencing errors. No output written to a.out
Now consider this code:
#include <string>
#include <list>
int main()
{
std::list<int> l;
std::string s(l); // error here
}
Specifying -filt=no%stdlib results in the following output:
Error: Cannot use std::list<int, std::allocator<int>> to initialize std::basic_string<char, std::char_traits<char>, std::allocator<char>>.
Specifying -filt=stdlib results in the following output:
Error: Cannot use std::list<int> to initialize std::string .
When you specify no%names, neither returns nor no%returns has an effect. That is, the following options are equivalent:
-filt=no%names
-filt=no%names,no%returns
-filt=no%names,returns
(SPARC) Enables automatic generation of floating-point, fused, multiply-add instructions. -fma=none disables generation of these instructions. -fma=fused allows the compiler to attempt to find opportunities to improve the performance of the code by using floating-point, fused, multiply-add instructions.
The default is -fma=none.
The minimum requirements are -xarch=sparcfmaf and an optimization level of at least -xO2 for the compiler to generate fused multiply-add instructions. The compiler marks the binary program if fused multiply-add instructions are generated in order to prevent the program from executing on platforms that do not support them.
Fused multiply-add instructions eliminate the intermediate rounding step between the multiply and the add. Consequently, programs may produce different results when compiled with -fma=fused, although precision will tend to be increased rather than decreased.
This is a macro that expands to —ftrap=common on x86, and —fns —ftrap=common on SPARC.
See –fns and –ftrap=common for more information.
SPARC: Enables/disables the SPARC nonstandard floating-point mode.
-fns=yes (or -fns) causes the nonstandard floating point mode to be enabled when a program begins execution.
This option provides a way of toggling the use of nonstandard or standard floating-point mode following some other macro option that includes –fns, such as –fast.
On some SPARC architectures, the nonstandard floating-point mode disables “gradual underflow,” causing tiny results to be flushed to zero rather than to produce subnormal numbers. It also causes subnormal operands to be silently replaced by zero.
On those SPARC architectures that do not support gradual underflow and subnormal numbers in hardware, -fns=yes (or -fns) can significantly improve the performance of some programs.
x86: Selects/deselects SSE flush-to-zero mode and, where available, denormals-are-zero mode.
This option causes subnormal results to be flushed to zero. Where available, this option also causes subnormal operands to be treated as zero.
This option has no effect on traditional x86 floating-point operations that do not utilize the SSE or SSE2 instruction set.
The -fns option can have the values listed in the following table.
Table A-7 -fns Values
|
If -fns is not specified, the nonstandard floating point mode is not enabled automatically. Standard IEEE 754 floating-point computation takes place, that is, underflows are gradual.
If only –fns is specified, –fns=yes is assumed.
In the following example, -fast expands to several options, one of which is -fns=yes which selects nonstandard floating-point mode. The subsequent -fns=no option overrides the initial setting and selects floating-point mode.
example% CC foo.cc -fast -fns=no
When nonstandard mode is enabled, floating-point arithmetic can produce results that do not conform to the requirements of the IEEE 754 standard.
If you compile one routine with the -fns option you should compile all routines of the program with the –fns option. Otherwise, you might get unexpected results.
This option is effective only when compiling the main program.
Use of the –fns=yes (or -fns) option might generate warning messages if your program encounters a floating-point error normally managed by the IEEE floating-point trap handlers.
Numerical Computation Guide, ieee_sun(3M) man page
x86: Sets the non-default floating-point precision mode.
The –fprecision option sets the rounding precision mode bits in the floating-point control word (FPCW). These bits control the precision to which the results of basic arithmetic operations (add, subtract, multiply, divide, and square root) are rounded.
p must be one of the values listed in the following table.
Table A-8 -fprecision Values
|
If p is single or double, this option causes the rounding precision mode to be set to single or double precision, respectively, when a program begins execution. If p is extended or the –fprecision option is not used, the rounding precision mode remains at the extended precision.
The single precision rounding mode causes results to be rounded to 24 significant bits, and double precision rounding mode causes results to be rounded to 53 significant bits. In the default extended precision mode, results are rounded to 64 significant bits. This mode controls only the precision to which results in registers are rounded, and it does not affect the range. All results in register are rounded using the full range of the extended double format. Results that are stored in memory are rounded to both the range and precision of the destination format, however.
The nominal precision of the float type is single. The nominal precision of the long double type is extended.
When the –fprecision option is not specified, the rounding precision mode defaults to extended.
This option is effective only on x86 systems and only if used when compiling the main program, but is ignored if compiling for 64–bit (-m64) or SSE2–enabled (-xarch=sse2) processors. It is also ignored on SPARC systems.
Sets the IEEE rounding mode in effect at startup.
This option sets the IEEE 754 rounding mode that can be used by the compiler in evaluating constant expressions. The rounding mode is established at runtime during the program initialization.
The meanings are the same as those for the ieee_flags subroutine, which can be used to change the mode at runtime.
r must be one of the values listed in the following table.
Table A-9 -fround Values
|
When the –fround option is not specified, the rounding mode defaults to -fround=nearest.
If you compile one routine with –fround=r, you must compile all routines of the program with the same –fround=r option. Otherwise, you might get unexpected results.
This option is effective only if used when compiling the main program.
Note that compiling with —xvector or —xlibmopt require default rounding. Programs that link with libraries compiled with either —xvector or —xlibmopt or both must ensure that default rounding is in effect.
Selects floating-point optimization preferences.
This option enables the optimizer to make simplifying assumptions concerning floating-point arithmetic.
If n is present, it must be 0, 1, or 2.
Table A-10 -fsimple Values
|
If –fsimple is not designated, the compiler uses -fsimple=0.
If -fsimple is designated but no value is given for n, the compiler uses -fsimple=1.
-fast implies– fsimple=2.
This option can break IEEE 754 conformance.
-fast
(x86) Forces precision of floating–point expressions.
This option causes the compiler to convert the value of a floating-point expression or function to the type on the left side of an assignment rather than leave the value in a register when the following is true:
The expression or function is assigned to a variable.
The expression is cast to a shorter floating-point type.
To turn off this option, use the –nofstore option. Both —fstore and —nofstore are ignored with a warning on SPARC platforms.
Due to roundoffs and truncation, the results can be different from those that are generated from the register values.
–nofstore
Sets the IEEE trapping mode in effect at startup but does not install a SIGFPE handler. You can use ieee_handler(3M) or fex_set_handling(3M) to simultaneously enable traps and install a SIGFPE handler. If you specify more than one value, the list is processed sequentially from left to right.
t can be one of the values listed in the following table.
Table A-11 The -ftrap Values
|
Note that the [no%] form of the option is used only to modify the meaning of the %all and common values, and must be used with one of these values, as shown in the example. The [no%] form of the option by itself does not explicitly cause a particular trap to be disabled.
If you do not specify –ftrap, the compiler assumes –ftrap=%none.
–ftrap=%all,no%inexact means to set all traps except inexact.
If you compile one routine with –ftrap=t, you should compile all routines of the program with the same -ftrap=t option. Otherwise, you might get unexpected results.
Use the -ftrap=inexact trap with caution. Use of– ftrap=inexact results in the trap being issued whenever a floating-point value cannot be represented exactly. For example, the following statement generates this condition:
x = 1.0 / 3.0;
This option is effective only if used when compiling the main program. Be cautious when using this option. If you want to enable the IEEE traps, use –ftrap=common.
ieee_handler(3M) and fex_set_handling(3M) man pages.
Build a dynamic shared library instead of an executable file.
All source files specified in the command line are compiled with -xcode=pic13 by default.
When building a shared library from files that involve templates and were compiled with the -instances=extern option, any template instances referenced by the .o files will be included from the template cache automatically.
If you are creating a shared object by specifying -G along with other compiler options that must be specified at both compile time and link time, make sure that those same options are also specified at both compile time and link time when you link with the resulting shared object.
When you create a shared object, all the object files compiled for 64–bit SPARC architectures must also be compiled with an explicit -xcode value as recommended in A.2.113 -xcode=a.
The following options are passed to the linker if –c (the compile-only option) is not specified:
–dy
–G
–R
Do not use ld -G to build shared libraries; use CC -G. The CC driver automatically passes several options to ld that are needed for C++.
When you use the -G option, the compiler does not pass any default -l options to ld. If you want the shared library to have a dependency on another shared library, you must pass the necessary -l option on the command line. For example, if you want the shared library to be dependent upon libCrun, you must pass -lCrun on the command line.
-dy, -xcode=pic13, –ztext, ld(1) man page, 14.3 Building Dynamic (Shared) Libraries.
Produces additional symbol table information for debugging with dbx(1) or the Debugger and for analysis with the Performance Analyzer analyzer(1).
Instructs both the compiler and the linker to prepare the file or program for debugging and for performance analysis.
The tasks include:
Producing detailed information, known as stabs, in the symbol table of the object files and the executable
Producing helper functions that the debugger can call to implement some of its features
Disabling the inline generation of functions if no optimization level is specified; that is, using this option implies the +d option if no optimization level is also specified. -g with any -O or -xO level does not disable inlining.
Disabling certain levels of optimization
If you use this option with –xOlevel (or its equivalent options, such as -O), you will get limited debugging information. For more information, see A.2.151 -xOlevel.
If you use this option and the optimization level is -xO4 or higher, the compiler provides best-effort symbolic information with full optimization. If you use —g without an optimization level specified, inlining of function calls will be disabled. (Inlining is enabled when an optimization level is specified with —g.)
When you specify this option, the +d option is specified automatically unless you also specify -O or -xO.
To use the full capabilities of the Performance Analyzer, compile with the -g option. While some performance analysis features do not require -g, you must compile with -g to view annotated source, some function level information, and compiler commentary messages. See the analyzer(1) man page and the Performance Analyzer manual for more information.
The commentary messages that are generated with -g describe the optimizations and transformations that the compiler made while compiling your program. Use the er_src(1) command to display the messages, which are interleaved with the source code.
If you compile and link your program in separate steps, then including the -g option in one step and excluding it from the other step will not affect the correctness of the program, but it will affect the ability to debug the program. Any module that is not compiled with -g (or -g0), but is linked with -g (or -g0) will not be prepared properly for debugging. Note that compiling the module that contains the function main with the -g option (or the -g0 option) is usually necessary for debugging.
+d,– g0,– xs, analyzer(1) man page, er_src(1) man page, ld(1) man page, Debugging a Program With dbx (for details about stabs), Performance Analyzer . manuals.
Compiles and links for debugging, but does not disable inlining.
This option is the same as –g, except that +d is disabled and dbx cannot use its step into feature on inlined functions.
If you specify -g0 and the optimization level is -xO3 or lower, the compiler provides best-effort symbolic information with almost full optimization. Tail-call optimization and back-end inlining are disabled.
+d, -g, Debugging a Program With dbx
Produce additional debugging information.
The —g3 option is the same as —g0 with additional debugging symbol table information to enable dbx to display the expansion of macros in the source code. This additional symbol table information can increase the size of the resulting .o and executable files compared to compiling with —g0.
Prints path names of included files.
On the standard error output (stderr), this option prints, one per line, the path name of each #include file contained in the current compilation.
Assigns the name name to the generated dynamic shared library.
This is a linker option passed to ld. In general, the name after -h should be exactly the same as the one after –o. A space between the –h and name is optional.
The compile-time loader assigns the specified name to the shared dynamic library you are creating. It records the name in the library file as the intrinsic name of the library. If there is no –hname option, then no intrinsic name is recorded in the library file.
Every executable file has a list of shared library files that are needed. When the runtime linker links the library into an executable file, the linker copies the intrinsic name from the library into that list of needed shared library files. If there is no intrinsic name of a shared library, then the linker copies the path of the shared library file instead.
When a shared library is built without the-h option, the runtime loader looks only for the file name of the library. You can replace the library with a different library with the same file name. If the shared library has an intrinsic name, the loader checks the intrinsic name when loading the file. If the intrinsic name does not match, the loader will not use the replacement file.
example% CC -G -o libx.so.1 -h libx.so.1 a.o b.o c.o
Add pathname to the #include file search path.
This option adds pathname to the list of directories that are searched for #include files with relative file names (those that do not begin with a slash).
The compiler searches for quote-included files (of the form #include "foo.h") in this order:
In the directory containing the source
In the directories named with -I options, if any
In the include directories for compiler-provided C++ header files, ANSI C header files, and special-purpose files
In the /usr/include directory
The compiler searches for bracket-included files (of the form #include <foo.h>) in this order:
In the directories named with -I options, if any
In the include directories for compiler-provided C++ header files, ANSI C header files, and special-purpose files
In the /usr/include directory
Note - If the spelling matches the name of a standard header file, also refer to 11.7.5 Standard Header Implementation .
The -I- option allows you to override the default search rules.
If you specify -library=no%Cstd, then the compiler does not include in its search path the compiler-provided header files that are associated with the C++ standard libraries. See 11.7 Replacing the C++ Standard Library.
If –ptipath is not used, the compiler looks for template files in –Ipathname.
Use –Ipathname instead of –ptipath.
This option accumulates instead of overrides.
Never specify the compiler installation area, /usr/include, /lib, or /usr/lib, as search directories.
-I-
Change the include-file search rules.
For include files of the form #include "foo.h", search the directories in the following order:
1. The directories named with -I options (both before and after -I-)
2. The directories for compiler-provided C++ header files, ANSI C header files, and special-purpose files
3. The /usr/include directory
For include files of the form #include <foo.h>, search the directories in the following order:
1. The directories named in the -I options that appear after -I-
2. The directories for compiler-provided C++ header files, ANSI C header files, and special-purpose files
3. The /usr/include directory
Note - If the name of the include file matches the name of a standard header, also refer to 11.7.5 Standard Header Implementation .
The following example shows the results of using -I- when compiling prog.cc.
prog.cc #include "a.h" #include <b.h> #include "c.h" c.h #ifndef _C_H_1 #define _C_H_1 int c1; #endif inc/a.h #ifndef _A_H #define _A_H #include "c.h" int a; #endif inc/b.h #ifndef _B_H #define _B_H #include <c.h> int b; #endif inc/c.h #ifndef _C_H_2 #define _C_H_2 int c2; #endif
The following command shows the default behavior of searching the current directory (the directory of the including file) for include statements of the form #include "foo.h". When processing the #include "c.h" statement in inc/a.h, the compiler includes the c.h header file from the inc subdirectory. When processing the #include "c.h" statement in prog.cc, the compiler includes the c.h file from the directory containing prog.cc. Note that the -H option instructs the compiler to print the paths of the included files.
example% CC -c -Iinc -H prog.cc
inc/a.h
inc/c.h
inc/b.h
inc/c.h
c.h
The next command shows the effect of the -I- option. The compiler does not look in the including directory first when it processes statements of the form #include "foo.h". Instead, it searches the directories named by the -I options in the order that they appear in the command line. When processing the #include "c.h" statement in inc/a.h, the compiler includes the ./c.h header file instead of the inc/c.h header file.
example% CC -c -I. -I- -Iinc -H prog.cc
inc/a.h
./c.h
inc/b.h
inc/c.h
./c.h
When -I- appears in the command line, the compiler never searches the current directory unless the directory is listed explicitly in a -I directive. This effect applies even for include statements of the form #include "foo.h".
Only the first -I- in a command line causes the described behavior.
Never specify the compiler installation area, /usr/include, /lib, or /usr/lib, as search directories.
Tells the linker, ld, to ignore any LD_LIBRARY_PATH and LD_LIBRARY_PATH_64 settings.
This option causes the compiler to treat filename as if it appears in the first line of a primary source file as a #include preprocessor directive. Consider the source file t.c:
main()
{
...
}
If you compile t.c with the command cc -include t.h t.c, the compilation proceeds as if the source file contains the following:
#include "t.h"
main()
{
...
}
The first directory the compiler searches for filename is the current working directory and not the directory containing the main source file, as is the case when a file is explicitly included. For example, the following directory structure contains two header files with the same name, but at different locations:
foo/
t.c
t.h
bar/
u.c
t.h
If your working directory is foo/bar and you compile with the command cc ../t.c -include t.h, the compiler includes t.h from foo/bar, not foo/ as would be the case with a #include directive from within the source file t.c.
If the compiler cannot find the file specified with -include in the current working directory, it searches the normal directory paths for the file. If you specify multiple -include options, the files are included in the order they appear on the command line.
Controls the placement and linkage of template instances.
a must be one of the values listed in the following table.
Table A-12 -instances Values
|
If –instances is not specified, –instances=global is assumed.
7.2.4 Template Instance Placement and Linkage
Use this option to inhibit the generation of template instances that are duplicated in a library, either shared or static, and the current object. In general, if your program shares large numbers of instances with libraries, try -instlib=filename and see whether compilation time improves.
Use the filename argument to specify a library that contains template instances that could be generated by the current compilation. The filename argument must contain a forward slash ’/’ character. For paths relative to the current directory, use dot-slash ’./’.
The -instlib=filename option has no default and is only used if you specify it. This option can be specified multiple times and accumulates.
Assume that the libfoo.a and libbar.so libraries instantiate many template instances that are shared with your source file a.cc. Adding -instlib=filename and specifying the libraries helps reduce compile time by avoiding the redundancy.
example% CC -c -instlib=./libfoo.a -instlib=./libbar.so a.cc
When you compile with -g, if the library specified with -instlib=file is not compiled with -g, those template instances will not be debuggable. The workaround is to avoid -instlib=file when you use -g.
If you specify a library with -instlib, you must link with that library.
-template, -instances, -pti
SPARC: (Obsolete) Same as –xcode=pic32.
x86: Same as –Kpic.
Use this option to compile source files when building a shared library. Each reference to a global datum is generated as a dereference of a pointer in the global offset table. Each function call is generated in program counter (PC)-relative addressing mode through a procedure linkage table.
SPARC: (Obsolete) Same as –xcode=pic13.
x86: Compiles with position-independent code.
Use this option to compile source files when building a shared library. Each reference to a global datum is generated as a dereference of a pointer in the global offset table. Each function call is generated in program counter (PC)-relative addressing mode through a procedure linkage table.
Retains temporary files created during compilation.
Along with –verbose=diags, this option is useful for debugging.
–v, –verbose
Adds path to the list of directories to search for libraries.
This option is passed to ld. The directory that is named by path is searched before compiler-provided directories.
This option accumulates instead of overrides.
Never specify the compiler installation area, /usr/include, /lib, or /usr/lib, as search directories.
Adds library liblib.a or liblib.so to the linker’s list of search libraries.
This option is passed to ld. Libraries generally have names such as liblib.a or liblib.so, where the lib and .a or .so parts are required. You should specify the lib part with this option. You can put as many libraries as you want on a single command line. Libraries are searched in the order specified with –Ldir.
Use this option after your object file name.
This option accumulates instead of overrides.
Put -lx after the list of sources and objects to ensure that libraries are searched in the correct order.
To ensure proper library linking order, you must use -mt rather than -lthread to link with libthread.
–Ldir and -mt
Incorporates specified CC-provided libraries into compilation and linking.
Keyword l must be one of the values in the following table. The no% prefix disables the associated option.
Table A-13 -library Values
|
Standard mode (the default mode)
The libCstd library is always included unless it is specifically excluded using -library=%none or -library=no%Cstd, —library=stdcxx4 or -library=stlport4.
The libCrun library is always included unless it is specifically excluded using -library=no%Crun.
The libm library is always included, even if you specify -library=%none.
To link in standard mode without any C++ libraries (except libCrun):
example% CC -library=%none
To include the classic-iostreams Rogue Wave tools.h++ library in standard mode:
example% CC –library=rwtools7,iostream
To include the standard-iostreams Rogue Wave tools.h++ library in standard mode:
example% CC -library=rwtools7_std
If a library is specified with -library, the proper –I paths are set during compilation. The proper –L, –Y P, –R paths and –l options are set during linking.
This option accumulates instead of overrides.
When you use the interval arithmetic libraries, you must include one of the following libraries: libC, libCstd, or libiostream.
Use of the -library option ensures that the -l options for the specified libraries are handled in the right order. For example, the -l options are passed to ld in the order -lrwtool -liostream for both -library=rwtools7,iostream and -library=iostream,rwtools7.
The specified libraries are linked before the system support libraries are linked.
For —library=stdcxx4, the Apache stdcxx library must be installed in /usr/include and /usr/lib on Oracle Solaris platforms.
You cannot use -library=sunperf and -xlic_lib=sunperf on the same command line.
You can use at most only one of -library=stlport4, -library=stdcxx4, or -library=Cstd options on any command line.
Only one Rogue Wave tools library can be used at a time and you cannot use any Rogue Wave tools library with -library=stlport4 or -library=stdcxx4.
When you include the classic-iostreams Rogue Wave tools library in standard mode (the default mode), you must also include libiostream (see the C++ Migration Guide for additional information). You can use the standard-iostreams Rogue Wave tools library in standard mode only. The following command examples show both valid and invalid use of the Rogue Wave tools.h++ library options.
% CC -library=rwtools7,iostream foo.cc <-- valid, classic iostreams % CC -library=rwtools7 foo.cc <-- invalid % CC -library=rwtools7_std foo.cc <-- valid, standard iostreams % CC -library=rwtools7_std,iostream foo.cc <-- invalid
If you include both libCstd and libiostream, you must be careful to not use the old and new forms of iostreams within a program to access the same file (for example, cout and std::cout). Mixing standard iostreams and classic iostreams in the same program is likely to cause problems if the same file is accessed from both classic and standard iostream code.
Standard-mode programs that do not link Crun or any of the Cstd or stlport4 libraries cannot use all features of the C++ language.
If -xnolib is specified, -library is ignored.
If you compile and link in separate steps, the set of -library options that appear in the compile command must appear in the link command.
The stlport4, Cstd, and iostream libraries provide their own implementation of I/O streams. Specifying more than one of these with the -library option can result in undefined program behavior. For more information about using STLport’s implementation, see 12.2 STLport.
The set of libraries is not stable and might change from release to release.
See 11.4.1.1 Note About Classic iostreams and Legacy RogueWave Tools
–I, –l, –R, –staticlib, -xia, -xlang, –xnolib, Caveats:, 12.2.1 Redistribution and Supported STLport Libraries, Tools.h++ User’s Guide.
For information about using the -library=no%cstd option to enable use of your own C++ standard library, see 11.7 Replacing the C++ Standard Library.
Specifies the memory model for the compiled binary object.
Use -m32 to create 32-bit executables and shared libraries. Use -m64 to create 64-bit executables and shared libraries.
The ILP32 memory model (32-bit int, long, pointer data types) is the default on all Oracle Solaris platforms and on Linux platforms that are not 64-bit enabled. The LP64 memory model (64-bit long, pointer data types) is the default on Linux platforms that are 64-bit enabled. -m64 is permitted only on platforms that are enabled for the LP64 model.
Object files or libraries compiled with -m32 cannot be linked with object files or libraries compiled with-m64.
Modules that are compiled with -m32|-m64 must also be linked with -m32|-m64. For a complete list of compiler options that must be specified at both compile time and link time, see 3.3.3 Compile-Time and Link-Time Options.
Applications that use large amounts of static data on 64–bit platforms (-m64) may also require -xmodel=medium. Be aware that some Linux platforms do not support the medium model.
Note that in previous compiler releases, the memory model, ILP32 or LP64, was implied by the choice of the instruction set with -xarch. Starting with the Solaris Studio 12 compilers just adding -m64 to the command line on most platforms is the correct way to create 64-bit objects.
On Oracle Solaris, -m32 is the default. On Linux systems supporting 64-bit programs, -m64 -xarch=sse2 is the default.
-xarch.
Removes duplicate strings from the ELF .comment section of the object file. When you use the -mc option, the mcs —c command is invoked. See the mcs(1) man page for details.
SPARC: Obsolete. This option should not be used. Use —xmemalign=2i instead..
Removes all strings from the .comment section of the object file and, if string is supplied, places string in that section. If the string contains blanks, the string must be enclosed in quotation marks. When you use this option, the command mcs -d [-a string] is invoked.
Use this option to compile and link multithreaded code using Oracle Solaris threads or POSIX threads API. The -mt=yes option assures that libraries are linked in the appropriate order.
This option passes -D_REENTRANT to the preprocessor.
To use Oracle Solaris threads, include the thread.h header file and compile with the —mt=yes option. To use POSIX threads on Oracle Solaris platforms, include the pthread.h header file and compile with the —mt=yes —lpthread options.
On Linux platforms, only the POSIX threads API is available. (There is no libthread on Linux platforms.) Consequently, —mt=yes on Linux platforms adds —lpthread instead of —lthread. To use POSIX threads on Linux platforms, compile with —mt=yes.
Note that when compiling with —G, neither —lthread nor —lpthread are automatically included by —mt=yes. You will need to explicitly list these libraries when building a shared library.
The —xopenmp option (for using the OpenMP shared-memory parallelization API) includes —mt=yes automatically.
If you compile with -mt=yes and link in a separate step, you must use the -mt=yes option in the link step as well as the compile step. If you compile and link one translation unit with -mt, you must compile and link all units of the program with -mt
-mt=yes is the default behavior of the compiler. If this behavior is not desired, compile with —mt=no.
The option —mt is equivalent to —mt=yes.
–xnolib, and the Oracle Solaris Multithreaded Programming Guide and Linker and Libraries Guide
Same as –xtarget=native.
x86: Cancel -fstore on command line.
Cancels forcing expressions to have the precision of the destination variable invoked by -fstore. -nofstore is invoked by -fast. -fstore is the usual default.
–fstore
Does not build a runtime search path for shared libraries into the executable.
If an executable file uses shared libraries, then the compiler normally builds in a path that points the runtime linker to those shared libraries. To do so, the compiler passes the –R option to ld. The path depends on the directory where you have installed the compiler.
This option is recommended for building executables that will be shipped to customers who might use a different path for the shared libraries that are referenced by the program. Refer to 11.6 Using Shared Libraries
If you use any shared libraries under the compiler installed area and you also use –norunpath, then you should either use the –R option at link time or set the environment variable LD_LIBRARY_PATH at runtime to specify the location of the shared libraries. Doing so enables the runtime linker to find the shared libraries.
The -O macro expands to -xO3. (Some previous releases expanded —O to –xO2).
The change in default yields higher runtime performance. However, -xO3 may be inappropriate for programs that rely on all variables being automatically considered volatile. Typical programs that might have this assumption are device drivers and older multithreaded applications that implement their own synchronization primitives. The workaround is to compile with -xO2 instead of -O.
Sets the name of the output file or the executable file to filename.
When the compiler must store template instances, it stores them in the template repository in the output file’s directory. For example, the following command writes the object file to ./sub/a.o and writes template instances into the repository contained within ./sub/SunWS_cache.
example% CC -instances=extern -o sub/a.o a.cc
The compiler reads from the template repositories corresponding to the object files that it reads. For example, the following command reads from ./sub1/SunWS_Cache and ./sub2/SunWS_cache, and, if necessary, writes to ./SunWS_cache.
example% CC -instances=extern sub1/a.o sub2/b.o
For more information, see 7.4 Template Repository.
The filename must have the appropriate suffix for the type of file to be produced by the compilation. When used with -c, filename specifies the target .o object file; with -G it specifies the target .so library file. This option and its argument are passed to ld.
filename cannot be the same file as the source file because the CC driver does not overwrite the source file.
Ignore nonstandard preprocessor asserts.
If +p is not present, the compiler recognizes nonstandard preprocessor asserts.
If +p is used, the following macros are not defined:
sun
unix
sparc
i386
Only preprocesses source; does not compile. (Outputs a file with a .i suffix.)
This option does not include preprocessor-type line number information in the output.
–E
Obsolete, see A.2.159 -xpg.
x86: Replace with –xtarget=pentium.
x86: Same as –Kpic.
SPARC: Same as –xcode=pic13.
x86: Same as -Kpic.
Same as –template=wholeclass.
Specifies an additional search directory for template source.
This option is an alternative to the normal search path set by –Ipathname. If the -ptipath option is used, the compiler looks for template definition files on this path and ignores the –Ipathname option.
Using the –Ipathname option instead of –ptipath produces less confusion.
This option accumulates instead of overrides.
–Ipathname, and 7.5.2 Definitions Search Path
Same as –instances=static.
Same as –verbose=template.
Passes option to the compilation phase.
To pass multiple options, specify them in order as a comma-separated list. Options that are passed to components with -Qoption might be reordered. Options that the driver recognizes are kept in the correct order. Do not use -Qoption for options that the driver already recognizes. For example, the C++ compiler recognizes the -z option for the linker (ld). If you issue a command like the following example, the -z options are passed in order to the linker.
CC -G -zallextract mylib.a -zdefaultextract ... // correct
But if you specify the command like as in the following example, the -z options can be reordered, giving incorrect results.
CC -G -Qoption ld -zallextract mylib.a -Qoption ld -zdefaultextract ... // error
phase must have one of the values listed in the following table.
Table A-14 -Qoption Values
|
In the following command , when ld is invoked by the CC driver, –Qoption passes the –i and –m options to ld.
example% CC -Qoption ld -i,-m test.c
Be careful to avoid unintended effects. For example, the following sequence of options:
-Qoption ccfe -features=bool,iddollar
are interpreted as:
-Qoption ccfe -features=bool -Qoption ccfe iddollar
The correct usage is
-Qoption ccfe -features=bool,-features=iddollar
These features do not require —Qoption, and are used only as an example.
Same as –Qoption.
Causes the CC driver to produce output of the type sourcetype.
Sourcetype suffixes are defined in the following table:
Table A-15 -Qproduce Values
|
Same as –Qproduce.
Builds dynamic library search paths into the executable file.
This option is passed to ld.
If the -R option is not present, the library search path that is recorded in the output object and passed to the runtime linker depends upon the target architecture instruction specified by the -xarch option. When -xarch is not present, -xarch=generic is assumed.
Examine the output from —dryrun and the —R option passed to the linker, ld, to see the default paths assumed by the compiler.
This option accumulates instead of overrides.
If the LD_RUN_PATH environment variable is defined and the –R option is specified, then the path from –R is scanned and the path from LD_RUN_PATH is ignored.
–norunpath, Linker and Libraries Guide
Compiles and generates only assembly code.
This option causes the CC driver to compile the program and output an assembly source file, without assembling the program. The assembly source file is named with a .s suffix.
Strips the symbol table from the executable file.
This option removes all symbol information from output executable files. This option is passed to ld.
Indicates which C++ libraries are to be linked statically, as specified by the -library option (including its defaults), by the -xlang option, and by the -xia option.
l must be one of the values listed in the following table.
Table A-16 -staticlib Values
|
If –staticlib is not specified, –staticlib=%none is assumed.
The following command links libCrun statically because Crun is a default value for –library:
example% CC –staticlib=Crun (correct)
However, the following command does not link libgc because libgc is not linked unless explicitly specified with the -library option:
example% CC –staticlib=gc (incorrect)
To link libgc statically, use the following command:
example% CC -library=gc -staticlib=gc (correct)
With the following command, the librwtool library is linked dynamically. Because librwtool is not a default library and is not selected using the -library option, -staticlib has no effect:
example% CC -lrwtool -library=iostream \ -staticlib=rwtools7 (incorrect)
The following command links the librwtool library statically:
example% CC -library=rwtools7,iostream -staticlib=rwtools7 (correct)
The following command will link the Sun Performance Libraries dynamically because -library=sunperf must be used in conjunction with -staticlib=sunperf in order for the -staticlib option to have an effect on the linking of these libraries:
example% CC -xlic_lib=sunperf -staticlib=sunperf (incorrect)
This command links the Sun Performance Libraries statically:
example% CC -library=sunperf -staticlib=sunperf (correct)
This option accumulates instead of overrides.
The -staticlib option only works for the C++ libraries that are selected explicitly with the -xia option, the -xlang option, and the -library option, in addition to the C++ libraries that are selected implicitly by default. Cstd and Crun are selected by default.
The set of allowable values for library is not stable and might change from release to release.
On Oracle Solaris platforms, system libraries are not available as static libraries.
-library, 11.5 Statically Linking Standard Libraries
Use this option when your runtime performance is degraded due to the synchronization between C++ iostreams and C stdio. Synchronization is needed only when you use iostreams to write to cout and stdio to write to stdout in the same program. The C++ standard requires synchronization so the C++ compiler turns it on by default. However, application performance is often much better without synchronization. If your program does not write to both cout and stdout, you can use the option -sync_stdio=no to turn off synchronization.
If you do not specify -sync_stdio, the compiler sets it to -sync_stdio=yes.
Consider the following example:
#include <stdio.h>
#include <iostream>
int main()
{
std::cout << "Hello ";
printf("beautiful ");
std::cout << "world!";
printf("\n");
}
With synchronization, the program prints on a line by itself
Hello beautiful world! :
Without synchronization, the output gets scrambled.
This option is only effective for linking of executables, not for libraries.
Defines the directory for temporary files.
This option sets the path name of the directory for storing the temporary files which are generated during the compilation process. The compiler gives precedence to the value set by -temp over the value of TMPDIR.
–keeptmp
Enables/disables various template options.
opt must be one of the values listed in the following table.
Table A-17 -template Values
|
If the -template option is not specified, -template=no%wholeclass,extdef is assumed.
Consider the following code:
example% cat Example.cc
template <class T> struct S {
void imf() {}
static void smf() {}
};
template class S <int>;
int main() {
}
example%
When you specify -template=geninlinefuncs, even though the two member functions of S are not called in the program, they are generated in the object file.
example% CC -c -template=geninlinefuncs Example.cc
example% nm -C Example.o
Example.o:
[Index] Value Size Type Bind Other Shndx Name
[5] 0 0 NOTY GLOB 0 ABS __fsr_init_value
[1] 0 0 FILE LOCL 0 ABS b.c
[4] 16 32 FUNC GLOB 0 2 main
[3] 104 24 FUNC LOCL 0 2 void S<int>::imf()
[__1cBS4Ci_Dimf6M_v_]
[2] 64 20 FUNC LOCL 0 2 void S<int>::smf()
[__1cBS4Ci_Dsmf6F_v_]
7.2.2 Whole-Class Instantiation, 7.5 Template Definition Searching
Issue a stack trace if a severe error occurs in execution.
The -traceback option causes the executable to issue a stack trace to stderr, dump core, and exit if certain signals are generated by the program. If multiple threads generate a signal, a stack trace will only be produced for the first one.
To use traceback, add the -traceback option to the compiler command line when linking. The option is also accepted at compile-time but is ignored unless an executable binary is generated. Do not use -traceback with -G to create a shared library.
Table A-18 -traceback Options
|
If the option is not specified, the default is -traceback=%none
-traceback alone, without an = sign, implies -traceback=common
Note: If the core dump is not wanted, you may set the core dump size limit to zero using the following command:
% limit coredumpsize 0
The -traceback option has no effect on runtime performance.
Deletes initial definition of the preprocessor symbol name.
This option removes any initial definition of the macro symbol name created by -D on the command line including those implicitly placed there by the CC driver. This option has no effect on any other predefined macros, nor on macro definitions in source files.
To see the -D options that are placed on the command line by the CC driver, add the -dryrun option to your command line.
The following command undefines the predefined symbol __sun. Preprocessor statements in foo.cc such as #ifdef(__sun) will sense that the symbol is undefined.
example% CC -U__sun foo.cc
You can specify multiple -U options on the command line.
All -U options are processed after any -D options that are present. That is, if the same name is specified for both -D and -U on the command line, name is undefined, regardless of the order the options appear.
-D
Same as –verbose=version.
v must be one of the values listed in the following table. The no% prefix disables the associated option.
Table A-19 -verbose Values
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If –verbose is not specified, –verbose=%none is assumed.
This option accumulates instead of overrides.
Passes the argument arg to a specified component c.
Arguments must be separated from the preceding only by a comma. All -W arguments are passed after the rest of the command-line arguments. To include a comma as part of an argument, use the escape character \ (backslash) immediately before the comma. All -W arguments are passed after the regular command-line arguments.
For example, -Wa,-o,objfile passes -o and objfile to the assembler in that order. Also, -Wl,-I,name causes the linking phase to override the default name of the dynamic linker, /usr/lib/ld.so.1.
The order in which the arguments are passed to a tool with respect to the other specified command line options might change an subsequent compiler releases.
The possible values for c are listed in the following table.
Table A-20 -W Flags
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Note: You cannot use -Wd to pass CC options to the C++ compiler.
Identifies code that might have unintended consequences. The +w option no longer generates a warning if a function is too large to inline or if a declared program element is unused. These warnings do not identify real problems in the source, and were thus inappropriate to some development environments. Removing these warnings from +w enables more aggressive use of +w in those environments. These warnings are still available with the +w2 option.
This option generates additional warnings about constructs that are questionable in the following ways:
Nonportable
Likely to be mistakes
Inefficient
If +w is not specified, the compiler warns about constructs that are almost certainly problems.
–w, +w2
Emits all the warnings emitted by +w plus warnings about technical violations that are probably harmless but that might reduce the maximum portability of your program.
The +w2 option no longer warns about the use of implementation-dependent constructs in the system header files. Because the system header files are the implementation, the warning was inappropriate. Removing these warnings from +w2 enables more aggressive use of the option.
+w
Suppresses most warning messages.
This option causes the compiler not to print warning messages. However, some warnings, particularly warnings regarding serious anachronisms, cannot be suppressed.
+w
Pass arg to linker ld(1). Equivalent to —z arg
Same as –features=iddollar.
(Solaris x86/x64 only) The -xaddr32=yes compilation flag restricts the resulting executable or shared object to a 32-bit address space.
An executable that is compiled in this manner results in the creation of a process that is restricted to a 32-bit address space.
When -xaddr32=no is specified, a normal 64 bit binary is produced.
If the -xaddr32 option is not specified, -xaddr32=no is assumed.
If only -xaddr32 is specified -xaddr32=yes is assumed.
This option is only applicable to -m64 compilations and only on Oracle Solaris platforms supporting SF1_SUNW_ADDR32 software capability. Because Linux kernels do not support address space limitation, this option is not available on Linux.
When linking, if a single object file was compiled with -xaddr32=yes, the whole output file is assumed to be compiled with -xaddr32=yes.
A shared object that is restricted to a 32-bit address space must be loaded by a process that executes within a restricted 32-bit mode address space.
For more information, refer to the SF1_SUNW_ADDR32 software capabilities definition described in the Linker and Libraries Guide.
The C++ compiler can perform type-based alias-analysis and optimizations when you specify the following commands:
-xalias_level[=n]
where n is any, simple, or compatible.
At this level of analysis, the compiler assumes that any type may alias any other type. However, despite this assumption, some optimization is possible.
The compiler assumes that simple types are not aliased. Storage objects must have a dynamic type that is one of the following simple types:
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The storage object should only be accessed through lvalues of the following types:
The dynamic type of the object
A constant or volatile qualified version of the dynamic type of the object, a type that is the signed or unsigned type which corresponds to the dynamic type of the object
A type that is the signed or unsigned type which corresponds to the constant or volatile qualified version of the dynamic type of the object
An aggregate or union type that includes one of the aforementioned types among its members (including, recursively, a member of a subaggregate or contained union)
A char or unsigned char type.
The compiler assumes that layout-incompatible types are not aliased. A storage object is only accessed through lvalues of the following types:
The dynamic type of the object
A constant or volatile qualified version of the dynamic type of the object, a type that is the signed or unsigned type which corresponds to the dynamic type of the object
A type that is the signed or unsigned type which corresponds to the constant or volatile qualified version of the dynamic type of the object
An aggregate or union type that includes one of the aforementioned types among its members (including, recursively, a member of a subaggregate or contained union)
A type that is (possibly constant or volatile qualified) base class type of the dynamic type of the object
A char or unsigned char type.
The compiler assumes that the types of all references are layout-compatible with the dynamic type of the corresponding storage object. Two types are layout-compatible under the following conditions:
If two types are the same type
If two types differ only in constant or volatile qualification
If for each of the signed integer types a corresponding (but different) unsigned integer type exists, these corresponding types are layout compatible.
Two enumeration types are layout-compatible if they have the same underlying type.
Two plain old data (POD) struct types are layout compatible if they have the same number of members, and corresponding members (in order) have layout compatible types.
Two POD union types are layout compatible if they have the same number of members, and corresponding members (in any order) have layout compatible types.
References may be non-layout-compatible with the dynamic type of the storage object under limited circumstances:
If a POD union contains two or more POD structs that share a common initial sequence, and if the POD union object currently contains one of those POD structs, it is permitted to inspect the common initial part of any of them. Two POD structs share a common initial sequence if corresponding members have layout compatible types and, as applicable to bit fields, the same widths, for a sequence of one or more initial members.
A pointer to a POD struct object, suitably converted using a reinterpret_cast, points to its initial member, or if that member is a bit field, to the unit in which it resides.
If you do not specify -xalias_level, the compiler sets the option to -xalias_level=any. If you specify -xalias_level but do not provide a value, the compiler sets the option to -xalias_level=compatible.
The compiler does not perform type-based alias analysis at optimization level -xO2 and below.
If you are using reinterpret_cast or an equivalent old-style cast, the program may violate the assumptions of the analysis. Also, union type punning, as shown in the following example, violates the assumptions of the analysis.
union bitbucket{
int i;
float f;
};
int bitsof(float f){
bitbucket var;
var.f=3.6;
return var.i;
}
Produce a static analysis of the source code that can be viewed using the Oracle Solaris Studio Code Analyzer.
When compiling with —xanalyze=code and linking in a separate step, include —xanalyze=code also on the link step.
The default is —xanalyze=no. See the Oracle Solaris Studio Code Analyzer documentation for more information.
(Solaris only) Create binaries that can later be used by the optimization and observability tools binopt(1), code-analyzer(1), discover(1), collect(1), and uncover(1).
The default is -xannotate=yes. Specifying -xannotate without a value is equivalent to -xannotate=yes.
For optimal use of the optimization and observability tools, -xannotate=yes must be in effect at both compile and link time. Compile and link with -xannotate=no to produce slightly smaller binaries and libraries when optimization and observability tools will not be used.
This option is not available on Linux systems.
When building a C++ archive that uses templates, include in the archive those template functions that are instantiated in the template repository. The template repository is used only when at least one object file was compiled using the -instances=extern option. Compiling with —xar automatically adds those templates to the archive as needed.
However, since the compiler default is not to use a template cache, the —xar option is often not needed. You can use the plain ar(1) command to create archives (.a files) of C++ code unless some code was compiled with —instances=extern. In that case, or if you are not sure, use CC —xar instead of the ar command.
Specify -xar to invokes ar -c -r and create an archive from scratch.
The following command line archives the template functions contained in the library and object files.
example% CC -xar -o libmain.a a.o b.o c.o
Do not add .o files from the template database on the command line.
Do not use the ar command directly for building archives. Use CC –xar to ensure that template instantiations are automatically included in the archive.
ar(1) man page
Specifies the target instruction set architecture (ISA).
This option limits the code generated by the compiler to the instructions of the specified instruction set architecture. This option does not guarantee use of any target–specific instructions. However, use of this option may affect the portability of a binary program.
Note - Use the -m64 or -m32 option to specify the intended memory model, LP64 (64-bits) or ILP32 (32-bits) respectively. The -xarch option no longer indicates the memory model except for compatibility with previous releases, as indicated below.
Code using _asm statements or inline templates (.il files) that use architecture-specific instructions might require compiling with the appropriate —xarch value to avoid compilation errors.
If you compile and link in separate steps, make sure you specify the same value for -xarch in both steps. For complete list of all compiler options that must be specified at both compile time and at link time, see 3.3.3 Compile-Time and Link-Time Options.
The following table lists the -xarch keywords common to both SPARC and x86 platforms.
Table A-21 —xarch Flags for SPARC and x86
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The following table gives the details for each of the -xarch keywords on SPARC platforms.
Table A-22 -xarch Flags for SPARC Platforms
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Also note the following:
Object binary files (.o) compiled with generic,sparc, sparcvis2, sparcvis3, sparcfmaf, sparcima can be linked and can execute together, but can only run on a processor supporting all the instruction sets linked.
For any particular choice, the generated executable might not run or run much more slowly on legacy architectures. Also, because quad-precision (long double) floating-point instructions are not implemented in any of these instruction set architectures, the compiler does not use these instructions in the code it generates.
The following table lists the -xarch flags on x86 platforms.
Table A-23 -xarch Flags on x86
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If any part of a program is compiled or linked on an x86 platform with —m64, then all parts of the program must be compiled with one of these options as well. For details on the various Intel instruction set architectures (SSE, SSE2, SSE3, SSSE3, and so on) refer to the Intel-64 and IA-32 Intel Architecture Software Developer's Manual
See also 1.2 Special x86 Notes and 1.4 Binary Compatibility Verification.
Although this option can be used alone, it is part of the expansion of the -xtarget option and may be used to override the –xarch value that is set by a specific -xtarget option. For example, -xtarget=ultra2 expands to -xarch=v8plusa -xchip=ultra2 -xcache=16/32/1:512/64/1. In the following command -xarch=v8plusb overrides the -xarch=v8plusa that is set by the expansion of -xtarget=ultra2.
example% CC -xtarget=ultra2 -xarch=v8plusb foo.cc
Use of –compat[=4] with -xarch=generic64, -xarch=native64, -xarch=v9, -xarch=v9a, or -xarch=v9b is not supported.
If you use this option with optimization, the appropriate choice can provide good performance of the executable on the specified architecture. An inappropriate choice, however, might result in serious degradation of performance or in a binary program that is not executable on the intended target platform.
If you compile and link in separate steps, make sure you specify the same value for -xarch in both steps.
Enables automatic parallelization for multiple processors. Does dependence analysis (analyze loops for inter-iteration data dependence) and loop restructuring. If optimization is not at -xO3 or higher, optimization is raised to -xO3 and a warning is issued.
Avoid -xautopar if you do your own thread management.
To achieve faster execution, this option requires a multi-processor system. On a single-processor system, the resulting binary usually runs slower.
To run a parallelized program in a multithreaded environment, the environment variable OMP_NUM_THREADS must be set to a value greater than 1 prior to execution. If not set, the default is 2. To use more threads, set OMP_NUM_THREADS to a higher value. Set OMP_NUM_THREADS to 1 to run with just one thread. In general, set OMP_NUM_THREADS to the available number of virtual pro cessors on the running system, which can be determined by using the Oracle Solaris psrinfo(1) command.
If you use -xautopar and compile and link in one step, then linking automatically includes the microtasking library and the threads-safe C runtime library. If you use -xautopar and compile and link in separate steps, then you must also link with -xautopar.
(SPARC) This option is now obsolete and will be removed in a future release of the compiler. SeeA.2.103 -xannotate[=yes|no]
Instructs the compiler to prepare the binary for later optimizations, transformations and analysis. See the binopt(1) man page. This option may be used for building executables or shared objects. If you compile in separate steps, -xbinopt must appear on both compile and link steps:
example% cc -c -xO1 -xbinopt=prepare a.c b.c example% cc -o myprog -xbinopt=prepare a.o
If some source code is not available for compilation, this option may still be used to compile the remainder of the code. It should then be used in the link step that creates the final binary. In such a situation, only the code compiled with this option can be optimized, transformed or analyzed.
The default is -xbinopt=off.
This option must be used with optimization level -xO1 or higher to be effective. There is a modest increase in size of the binary when built with this option.
Compiling with -xbinopt=prepare and -g increases the size of the executable by including debugging information.
Enables or disables better optimization of standard library calls.
Use the -xbuiltin option to improve the optimization of code that calls standard library functions. This option lets the compiler substitute intrinsic functions or inline system functions where profitable for perfor mance. See the er_src(1) man page to learn how to read compiler commentary output to determine which functions were substituted by the compiler.
With —xbuiltin=%all, substitutions can cause the setting of errno to become unreliable. If your program depends on the value of errno, avoid this option.
—xbuiltin=%default only inlines functions that do not set errno. The value of errno is always correct at any optimization level, and can be checked reliably. With —xbuiltin=%default at —xO3 or lower, the compiler will determine which calls are profitable to inline, and not inline others.
The-xbuiltin=%none option results in the default compiler behavior, and the compiler does not do any special optimizations for built-in functions.
If you do not specify —xbuiltin, the default is —xbuiltin=%default when compiling with an optimization level —xO1 and higher, and —xbuiltin=%none at —xO0. If you specify —xbuiltin without an argument, the default is —xbuiltin=%all and the compiler substitutes intrinsics or inlines standard library functions much more aggressively.
Note that the —xbuiltin option only inlines global functions defined in system header files, never static functions defined by the user. User code that attempts to interpose on global functions may result in undefined behavior.
The expansion of the macro -fast includes -xbuiltin=%all.
The following compiler command requests special handling of the standard library calls.
example% CC -xbuiltin -c foo.cc
The following compiler command requests that there be no special handling of the standard library calls. Note that the expansion of the macro -fast includes -xbuiltin=%all.
example% CC -fast -xbuiltin=%none -c foo.cc
Defines cache properties for use by the optimizer. This option does not guarantee that any particular cache property is used.
Note - Although this option can be used alone, it is part of the expansion of the -xtarget option. Its primary use is to override a value supplied by the -xtarget option.
The optional property [/ti] sets the number of threads that can share the cache.
c must be one of the values listed in the following table.
Table A-24 -xcache Values
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The definitions of the cache properties si/li/ai/ti are described in the following table:
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For example, i=1 designates level 1 cache properties, s1/l1/a1.
If -xcache is not specified, the default -xcache=generic is assumed. This value directs the compiler to use cache properties for good performance on most SPARC processors without major performance degradation on any of them.
If you do not specify a value for t, the default is 1.
–xcache=16/32/4:1024/32/1 specifies the following values:
16 Kbytes, 32 bytes line size, four-way associativity
1024 Kbytes, 32 bytes line size, direct mapping associativity
–xtarget=t
The option is provided solely for the purpose of easing the migration of code from systems where the char type is defined as unsigned. Unless you are migrating from such a system, do not use this option. Only code that relies on the sign of a char type needs to be rewritten to explicitly specify signed or unsigned.
You can substitute one of the values in the following table for o.
Table A-25 The -xchar Values
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If you do not specify -xchar, the compiler assumes -xchar=s.
If you specify -xchar, but do not specify a value, the compiler assumes -xchar=s.
The -xchar option changes the range of values for the type char only for code compiled with -xchar. This option does not change the range of values for type char in any system routine or header file. In particular, the values of CHAR_MAX and CHAR_MIN, as defined by limits.h, do not change when this option is specified. Therefore, CHAR_MAX and CHAR_MIN no longer represent the range of values encodable in a plain char.
If you use -xchar=unsigned, be particularly careful when you compare a char against a predefined system macro because the value in the macro may be signed. This situation is most common for any routine that returns an error code which is accessed through a macro. Error codes are typically negative values so when you compare a char against the value from such a macro, the result is always false. A negative number can never be equal to any value of an unsigned type.
Never use -xchar to compile routines for any interface exported through a library. The Oracle Solaris ABI specifies type char as signed, and system libraries behave accordingly. The effect of making char unsigned has not been extensively tested with system libraries. Instead of using this option, modify your code so that it does not depend on whether type char is signed or unsigned. The sign variety of type char varies among compilers and operating systems.
Compiling with -xcheck=stkovf adds a runtime check for stack overflow of the main thread in a single-threaded program as well as slave-thread stacks in a multithreaded program. If a stack overflow is detected, a SIGSEGV is generated. See the sigaltstack(2) man page for information on how to handle a SIGSEGV caused by a stack overflow differently than other address-space violations.
i must be one of the values listed in the following table.
Table A-26 -xcheck Values
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If you do not specify -xcheck, the compiler defaults to -xcheck=%none.
If you specify -xcheck without any arguments, the compiler defaults to -xcheck=%none.
The -xcheck option does not accumulate on the command line. The compiler sets the flag in accordance with the last occurrence of the command.
Specifies target processor for use by the optimizer.
The –xchip option specifies timing properties by specifying the target processor. This option affects the following properties:
The ordering of instructions—that is, scheduling
The way the compiler uses branches
The instructions to use in cases where semantically equivalent alternatives are available
Note - Although this option can be used alone, it is part of the expansion of the -xtarget option. Its primary use is to override a value supplied by the -xtarget option.
c must be one of the values listed in the following two tables.
Table A-27 -xchip Values for SPARC Processors
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Table A-28 -xchip Values for x86/x64 Processors
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On most processors, generic is the default value that directs the compiler to use the best timing properties for good performance without major performance degradation on any of the processors.
(SPARC only) Specifies the code address space.
Note - You should build shared objects by specifying -xcode=pic13 or -xcode=pic32. Shared objects built without pic13 or pic32 will not work correctly, and might not build at all.
a must be one of the values listed in the following table.
Table A-29 -xcode Values
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To determine whether to use –xcode=pic13 or –xcode=pic32, check the size of the Global Offset Table (GOT) by using elfdump -c and look for the section header sh_name: .got. The sh_size value is the size of the GOT. If the GOT is less than 8,192 bytes, specify -xcode=pic13, otherwise specify -xcode=pic32. See the elfdump(1) man page for more information.
In general, use the following guidelines to determine how you should use -xcode:
If you are building an executable you should not use -xcode=pic13 or -xcode=pic32.
If you are building an archive library only for linking into executables you should not use -xcode=pic13 or -xcode=pic32.
If you are building a shared library, start with– xcode=pic13. Once the GOT size exceeds 8,192 bytes, use -xcode=pic32.
If you are building an archive library for linking into shared libraries you should only use -xcode=pic32.
The default is -xcode=abs32 for 32–bit architectures. The default for 64–bit architectures is -xcode=abs44.
When building shared dynamic libraries, the default -xcode values of abs44 and abs32 will not work with 64–bit architectures. Specify -xcode=pic13 or -xcode=pic32 instead. There are two nominal performance costs with -xcode=pic13 and -xcode=pic32 on SPARC:
A routine compiled with either -xcode=pic13 or -xcode=pic32 executes a few extra instructions upon entry to set a register to point at a table (_GLOBAL_OFFSET_TABLE_) used for accessing a shared library’s global or static variables.
Each access to a global or static variable involves an extra indirect memory reference through _GLOBAL_OFFSET_TABLE_. If the compile is done with -xcode=pic32, there are two additional instructions per global and static memory reference.
When considering the above costs, remember that the use of -xcode=pic13 and -xcode=pic32 can significantly reduce system memory requirements due to the effect of library code sharing. Every page of code in a shared library compiled -xcode=pic13 or– xcode=pic32 can be shared by every process that uses the library. If a page of code in a shared library contains even a single non-pic (that is, absolute) memory reference, the page becomes nonsharable, and a copy of the page must be created each time a program using the library is executed.
The easiest way to tell whether a .o file has been compiled with -xcode=pic13 or –xcode=pic32 is with the nm command:
% nm file.o | grep _GLOBAL_OFFSET_TABLE_ U _GLOBAL_OFFSET_TABLE_
A .o file containing position-independent code contains an unresolved external reference to _GLOBAL_OFFSET_TABLE_, as indicated by the letter U.
To determine whether to use -xcode=pic13 or -xcode=pic32, use nm to identify the number of distinct global and static variables used or defined in the library. If the size of _GLOBAL_OFFSET_TABLE_ is under 8,192 bytes, you can use -Kpic. Otherwise, you must use -xcode=pic32.
The compiler has migrated the format of debugger information from the stabs (“symbol table”) format to the dwarf format of the DWARF Debugging Information Format specification. The default setting is -xdebugformat=dwarf.
If you maintain software which reads debugging information, you now have the option to transition your tools from the stabs format to the dwarf format.
Use this option as a way of accessing the new format for the purpose of porting tools. You do not need to use this option unless you maintain software which reads debugger information, or unless a specific tool requires debugger information in either of these formats.
Table A-30 -xdebugformat Flags
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If you do not specify -xdebugformat, the compiler assumes -xdebugformat=dwarf. This option requires an argument.
This option affects the format of the data that is recorded with the -g option. Some small amount of debugging information is recorded even without -g, and the format of that information is also controlled with this option. So, -xdebugformat has an effect even when -g is not used.
The dbx and Performance Analyzer software understand both stabs and dwarf format so using this option does not have any effect on the functionality of either tool.
Note - Stabs format cannot represent all debug data now used by dbx, and some code might not generate debug data successfully using stabs.
See also the dumpstabs(1) and dwarfdump(1) man pages for more information.
Analyzes loops for inter-iteration data dependencies and does loop restructuring, including loop interchange, loop fusion, scalar replacement, and elimination of “dead array” assignments.
On SPARC processors, –xdepend defaults to –xdepend=on for all optimization levels –xO3 and above. Otherwise –xdepend defaults to –xdepend=off. Specifying an explicit setting of –xdepend overrides any default setting.
On x86 processors, –xdepend defaults to –xdepend=off. When —xdepend is specified and optimization is not at –xO3 or higher, the compiler raises the optmization to –xO3 and issues a warning.
Specifying –xdepend without an argument is equivalent to –xdepend=yes.
Dependency analysis is included in -xautopar. Dependency analysis is done at compile time.
Dependency analysis may help on single-processor systems. However, if you uese –xdepend on single-processor systems, you should not also specify –xautopar because the –xdepend optimization will be done for a multiprocessor system.
–xprefetch_auto_type
Use this option when you want to see how macros are behaving in your program. This option provides information such as macro defines, undefines, and instances of usage. It prints output to the standard error (stderr), based on the order in w hich macros are processed. The -xdumpmacros option is in effect through the end of the file or until it is overridden by the dumpmacros or end_dumpmacros pragma. See B.2.5 #pragma dumpmacros.
The following table lists the valid arguments for value. The prefix no% disables the associated value.
Table A-31 -xdumpmacros Values
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The option values accumulate, so specifying -xdumpmacros=sys -xdumpmacros=undefs has the same effect as -xdumpmacros=undefs,sys.
Note - The sub-options loc, conds, and sys are qualifiers for defs, undefs and use options. By themselves, loc, conds, and sys have no effect. For example, -xdumpmacros=loc,conds,sys has no effect.
Specifying -xdumpmacros without any arguments defaults to -xdumpmacros=defs,undefs,sys. The default when not specifying -xdumpmacros is -xdumpmacros=%none.
If you use the option -xdumpmacros=use,no%loc, the name of each macro that is used is printed only once. However, if you want more detail, use the option -xdumpmacros=use,loc so the location and macro name is printed every time a macro is used.
Consider the following file t.c:
example% cat t.c #ifdef FOO #undef FOO #define COMPUTE(a, b) a+b #else #define COMPUTE(a,b) a-b #endif int n = COMPUTE(5,2); int j = COMPUTE(7,1); #if COMPUTE(8,3) + NN + MM int k = 0; #endif
The following examples show the output for file t.c based on the defs, undefs, sys, and loc arguments.
example% CC -c -xdumpmacros -DFOO t.c #define __SunOS_5_9 1 #define __SUNPRO_CC 0x590 #define unix 1 #define sun 1 #define sparc 1 #define __sparc 1 #define __unix 1 #define __sun 1 #define __BUILTIN_VA_ARG_INCR 1 #define __SVR4 1 #define __SUNPRO_CC_COMPAT 5 #define __SUN_PREFETCH 1 #define FOO 1 #undef FOO #define COMPUTE(a, b) a + b example% CC -c -xdumpmacros=defs,undefs,loc -DFOO -UBAR t.c command line: #define __SunOS_5_9 1 command line: #define __SUNPRO_CC 0x590 command line: #define unix 1 command line: #define sun 1 command line: #define sparc 1 command line: #define __sparc 1 command line: #define __unix 1 command line: #define __sun 1 command line: #define __BUILTIN_VA_ARG_INCR 1 command line: #define __SVR4 1 command line: #define __SUNPRO_CC_COMPAT 5 command line: #define __SUN_PREFETCH 1 command line: #define FOO 1 command line: #undef BAR t.c, line 2: #undef FOO t.c, line 3: #define COMPUTE(a, b) a + b
The following examples show how the use, loc, and conds arguments report macro behavior in file t.c:
example% CC -c -xdumpmacros=use t.c used macro COMPUTE example% CC -c -xdumpmacros=use,loc t.c t.c, line 7: used macro COMPUTE t.c, line 8: used macro COMPUTE example% CC -c -xdumpmacros=use,conds t.c used macro FOO used macro COMPUTE used macro NN used macro MM example% CC -c -xdumpmacros=use,conds,loc t.c t.c, line 1: used macro FOO t.c, line 7: used macro COMPUTE t.c, line 8: used macro COMPUTE t.c, line 9: used macro COMPUTE t.c, line 9: used macro NN t.c, line 9: used macro MM
Consider the file y.c:
example% cat y.c #define X 1 #define Y X #define Z Y int a = Z;
The following example shows the output from -xdumpmacros=use,loc based on the macros in y.c:
example% CC -c -xdumpmacros=use,loc y.c y.c, line 4: used macro Z y.c, line 4: used macro Y y.c, line 4: used macro X
Pragma dumpmacros/end_dumpmacros overrides the scope of the -xdumpmacros command-line option.
Checks only for syntax and semantic errors. When you specify -xe, the compiler does not produce any object code. The output for -xe is directed to stderr.
Use the -xe option if you do not need the object files produced by compilation. For example, if you are trying to isolate the cause of an error message by deleting sections of code, you can speed the edit and compile cycle by using -xe.
–c
Enables optimal reordering of functions and variables by the linker.
This option instructs the compiler to place functions or data variables into separate section fragments, which enables the linker to reorder these sections to optimize program performance using directions in a mapfile specified by the linker’s -M option. Generally, this optimization is only effective when page fault time constitutes a significant fraction of program run time.
Reording of variables can help solve the following problems which negatively impact runtime performance:
Cache and page contention caused by unrelated variables that are near each other in memory
Unnecessarily large work-set size as a result of related variables which are not near each other in memory
Unnecessarily large work-set size as a result of unused copies of weak variables that decrease the effective data density
Reordering variables and functions for optimal performance requires the following operations:
Compiling and linking with -xF.
Following the instructions in the Performance Analyzer manual regarding how to generate a mapfile for functions or following the instructions in the Linker and Libraries Guide regarding how to generate a mapfile for data.
Relinking with the new mapfile by using the linker’s -M option.
Re-executing under the Analyzer to verify improvement.
v can be one or more of the values listed in the following table. The no% prefix disables the associated value.
Table A-32 -xF Values
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If you do not specify -xF, the default is -xF=%none. If you specify -xF without any arguments, the default is -xF=%none,func.
Using -xF=lcldata inhibits some address calculation optimizations, so you should only use this flag when it is experimentally justified.
The analyzer(1) and ld(1) man pages
Displays a brief description of each compiler option.
(SPARC only) Enables compiler support for hardware counter-based profiling.
When -xhwcprof is enabled, the compiler generates information that helps tools associate profiled load and store instructions with the data-types and structure members (in conjunction with symbolic information produced with -g to which they refer. It associates profile data with the data space of the target, rather than the instruction space. This option provides insight into behavior that is not easily obtained from instruction profiling alone.
You can compile a specified set of object files with -xhwcprof. However, -xhwcprof is most useful when applied to all object files in the application, providing complete coverage to identify and correlate all memory references distributed in the application’s object files.
If you are compiling and linking in separate steps, use -xhwcprof at link time as well. Future extensions to -xhwcprof may require its use at link time.
An instance of -xhwcprof=enable or -xhwcprof=disable overrides all previous instances of -xhwcprof in the same command line.
-xhwcprof is disabled by default. Specifying -xhwcprof without any arguments is the equivalent to -xhwcprof=enable.
-xhwcprof requires that optimization is turned on and that the DWARF debug data format is selected. Note that DWARF format (-xdebugformat=dwarf) is now the default.
The combination of -xhwcprof and -g increases compiler temporary file storage requirements by more than the sum of the increases resulting from either -xhwcprof and -g alone.
The following command compiles example.cc and specifies support for hardware counter profiling and symbolic analysis of data types and structure members using DWARF symbols:
example% CC -c -O -xhwcprof -g -xdebugformat=dwarf example.cc
For more information about hardware counter-based profiling, see the Performance Analyzer manual.
Links the appropriate interval arithmetic libraries and sets a suitable floating-point environment.
Note - The C++ interval arithmetic library is compatible with interval arithmetic as implemented in the Fortran compiler.
On x86 platforms, this optioin requires support of SSE2 instruction set.
The -xia option is a macro that expands to -fsimple=0 -ftrap=%none -fns=no -library=interval. If you use intervals and override what is set by -xia by specifying a different flag for -fsimple, -ftrap, -fns or -library, you may cause the compiler to exhibit incorrect behavior.
To use the interval arithmetic libraries, include <suninterval.h>.
When you use the interval arithmetic libraries, you must include one of the following libraries: Cstd, or iostreams. See -library for information about including these libraries.
If you use intervals and you specify different values for -fsimple, -ftrap, or -fns, then your program may exhibit incorrect behavior.
C++ interval arithmetic is experimental and evolving. The specifics might change from release to release.
-library
Specifies which user-written routines can be inlined by the optimizer at -xO3 levels or higher.
func-spec must be one of the values listed in the following table.
Table A-33 -xinline Values
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Only routines in the file being compiled are considered for inlining unless you use -xipo[=1|2]. The optimizer decides which of these routines are appropriate for inlining.
If the -xinline option is not specified, the compiler assumes -xinline=%auto.
If -xinline= is specified with no arguments, no functions are inlined regardless of the optimization level.
To enable automatic inlining while disabling inlining of the function declared int foo(), use the following command:
example% CC -xO5 -xinline=%auto,no%__1cDfoo6F_i_ -c a.cc
To strongly request the inlining of the function declared as int foo(), and to make all other functions as the candidates for inlining, use the following command:
example% CC -xO5 -xinline=%auto,__1cDfoo6F_i_ -c a.cc
To strongly request the inlining of the function declared as int foo(), and to not allow inlining of any other functions, use the following command:
example% CC -xO5 -xinline=__1cDfoo6F_i_ -c a.cc
The -xinline option has no effect for optimization levels below -xO3. At -xO4 and higher, the optimizer decides which functions should be inlined, and does so without the -xinline option being specified. At -xO4 and higher, the compiler also attempts to determine which functions will improve performance if they are inlined.
A routine is inlined if any of the following conditions apply.
Optimization is -xO3 or greater
Inlining is judged to be profitable and safe
The function is in the file being compiled, or the function is in a file that was compiled with -xipo[=1|2]
If you force the inlining of a function with -xinline, you might actually diminish performance.
Specify this option to compile and instrument your program for analysis by the Thread Analyzer. For more information on the Thread Analyzer, see the tha(1) man page for details.
You can then use the Performance Analyzer to run the instrumented program with collect -r races to create a data-race-detection experiment. You can run the instrumented code standalone but it runs more slowly.
You can specify -xinstrument=no%datarace to turn off preparation of source code for the thread analyzer. This is the default.
You cannot specify -xinstrument without an argument.
If you compile and link in separate steps, you must specify -xinstrument=datarace in both the compilation and linking steps.
This option defines the preprocessor token __THA_NOTIFY. You can specify #ifdef __THA_NOTIFY to guard calls to libtha(3) routines.
This option also sets -g.
Performs interprocedural optimizations.
The -xipo option performs partial-program optimizations by invoking an interprocedural analysis pass. It performs optimizations across all object files in the link step, and the optimizations are not limited to just the source files on the compile command. However, whole-program optimizations performed with -xipo do not include assembly (.s) source files.
The -xipo option is particularly useful when compiling and linking large multifile applications. Object files compiled with this flag have analysis information compiled within them that enables interprocedural analysis across source and precompiled program files. However, analysis and optimization is limited to the object files compiled with -xipo, and does not extend to object files or libraries.
The -xipo option can have the values listed in the following table.
Table A-34 The -xipo Values
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If -xipo is not specified, -xipo=0 is assumed.
If only -xipo is specified, -xipo=1 is assumed.
The following example compiles and links in the same step.
example% CC -xipo -xO4 -o prog part1.cc part2.cc part3.cc
The optimizer performs crossfile inlining across all three source files in the final link step. The compilation of the source files need not all take place in a single compilation and could be accomplished over a number of separate compilations, each specifying the -xipo option.
The following example compiles and links in separate steps.
example% CC -xipo -xO4 -c part1.cc part2.cc example% CC -xipo -xO4 -c part3.cc example% CC -xipo -xO4 -o prog part1.o part2.o part3.o
The object files created in the compile steps have additional analysis information compiled within them to permit crossfile optimizations to take place at the link step.
The compiler tries to perform whole-program analysis and optimizations as it works with the set of object files in the link step. The compiler makes the following two assumptions for any function or subroutine foo() defined in this set of object files:
foo() is not called explicitly by another routine that is defined outside this set of object files at runtime.
The calls to foo() from any routine in the set of object files are not interposed upon by a different version of foo() defined outside this set of object files.
Do not compile with -xipo=2, if the first assumption is not true for the given application.
Do not compile with either -xipo=1 or -xipo=2, if the second assumption is not true.
As an example, consider interposing on the function malloc() with your own version and compiling with -xipo=2. All the functions in any library that reference malloc() that are linked with your code have to be compiled with -xipo=2 also and their object files need to participate in the link step. Because this strategy might not be possible for system libraries, do not compile your version of malloc() with -xipo=2.
As another example, suppose that you build a shared library with two external calls, foo() and bar() inside two different source files. Furthermore, suppose that bar() calls foo(). If foo() could be interposed at runtime, do not compile the source file for foo() or for bar() with -xipo=1 or -xipo=2. Otherwise, foo() could be inlined into bar(), which could cause incorrect results.
The -xipo option requires at least optimization level -xO4.
When compiling and linking are performed in separate steps, -xipo must be specified in both steps to be effective.
Objects that are compiled without -xipo can be linked freely with objects that are compiled with -xipo.
Libraries do not participate in crossfile interprocedural analysis, even when they are compiled with -xipo, as shown in the following example.
example% CC -xipo -xO4 one.cc two.cc three.cc example% CC -xar -o mylib.a one.o two.o three.o ... example% CC -xipo -xO4 -o myprog main.cc four.cc mylib.a
In this example, interprocedural optimizations will be performed between one.cc, two.cc and three.cc, and between main.cc and four.cc, but not between main.cc or four.cc and the routines in mylib.a. (The first compilation may generate warnings about undefined symbols, but the interprocedural optimizations will be performed because it is a compile and link step.)
The -xipo option generates significantly larger object files due to the additional information needed to perform optimizations across files. However, this additional information does not become part of the final executable binary file. Any increase in the size of the executable program will be due to the additional optimizations performed.
-xjobs
The -xipo_archive option enables the compiler to optimize object files that are passed to the linker with object files that were compiled with -xipo and that reside in the archive library (.a) before producing an executable. Any object files contained in the library that were optimized during the compilation are replaced with their optimized version.
The following table lists possible values for a.
Table A-35 -xipo_archive Flags
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If you do not specify a setting for -xipo_archive, the compiler sets it to -xipo_archive=none.
You cannot specify -xipo_archive without a flag.
Disable or set interpretation of #pragma ivdep pragmas (ignore vector dependencies).
The ivdep pragmas tell a compiler to ignore some or all loop-carried dependences on array references that it finds in a loop for purposes of optimization. This enables a compiler to perform various loop optimizations such as microvectorization, distribution, software pipelining, and so on, which would not be otherwise possible. It is used in cases where the user knows either that the dependences do not matter or that they never occur in practice.
The interpretation of #pragma ivdep directives depend upon the value of the —xivdep option.
The following list gives the values for p and their meaning.
ignore assumed loop-carried vector dependences
ignore all loop-carried vector dependences
ignore assumed backward loop-carried vector dependences
ignore all backward loop-carried vector dependences
do not ignore any dependences (disables ivdep pragmas)
These interpretations are provided for compatibility with other vendor's interpretations of the ivdep pragma.
Specify the -xjobs option to set how many processes the compiler creates to complete its work. This option can reduce the build time on a multi-processor machine. Currently, -xjobs works only with the -xipo option. When you specify -xjobs=n, the interprocedural optimizer uses n as the maximum number of code generator instances it can invoke to compile different files.
You must always specify -xjobs with a value. Otherwise, an error diagnostic is issued and compilation aborts.
Generally, a safe value for n is 1.5 multiplied by the number of available processors. Using a value that is many times the number of available processors can degrade performance because of context-switching overheads among spawned jobs. Also, using a very high number can exhaust the limits of system resources such as swap space.
Multiple instances of -xjobs on the command line override each other until the right-most instance is reached.
The following example compiles more quickly on a system with two processors than the same command without the -xjobs option.
example% CC -xipo -xO4 -xjobs=3 t1.cc t2.cc t3.cc
Prohibit stack related optimizations for the named functions (name).
Prohibit stack related optimizations for all the code.
Allow stack related optimizations for all the code.
This option is accumulative and can appear multiple times on the command line. For example, —xkeepframe=%all —xkeepframe=no%func1 indicates that the stack frame should be kept for all functions except func1. Also, —xkeepframe overrides —xregs=frameptr. For example, —xkeepframe=%all —xregs=frameptr indicates that the stack should be kept for all functions, but the optimizations for —xregs=frameptr would be ignored.
If not specified on the command line, the compiler assumes -xkeepframe=%none as the default. If specified but without a value, the compiler assumes -xkeepframe=%all
Includes the appropriate runtime libraries and ensures the proper runtime environment for the specified language.
language must be either f77, f90, f95, or c99.
The f90 and f95 arguments are equivalent. The c99 argument invokes ISO 9899:1999 C programming language behavior for objects that were compiled with cc -xc99=%all and are being linked with CC.
The -xlang=f90 and -xlang=f95 options imply -library=f90, and the -xlang=f77 option implies -library=f77. However, the -library=f77 and -library=f90 options are not sufficient for mixed-language linking because only the -xlang option ensures the proper runtime environment.
To determine which driver to use for mixed-language linking, use the following language hierarchy:
C++
Fortran 95 (or Fortran 90)
Fortran 77
C or C99
When linking Fortran 95, Fortran 77, and C++ object files together, use the driver of the highest language. For example, use the following C++ compiler command to link C++ and Fortran 95 object files:
example% CC -xlang=f95...
To link Fortran 95 and Fortran 77 object files, use the Fortran 95 driver, as follows:
example% f95 -xlang=f77...
You cannot use the -xlang option and the -xlic_lib option in the same compiler command. If you are using -xlang and you need to link in the Sun Performance Libraries, use -library=sunperf instead.
Do not use -xnolib with -xlang.
If you are mixing parallel Fortran objects with C++ objects, the link line must specify the -mt flag.
-library, -staticlib
Specify the -xldscope option to change the default linker scoping for the definition of extern symbols. Changing the default can result in faster and safer shared libraries and executables because the implementation are better hidden.
The following table lists the possible values for v.
Table A-36 The -xldscope Values
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If you do not specify -xldscope, the compiler assumes -xldscope=global. If you specify -xldscope without any values, the compiler issues an error. Multiple instances of this option on the command line override each other until the right-most instance is reached.
If you intend to allow a client to override a function in a library, you must be sure that the function is not generated inline during the library build. The compiler inlines a function in the following situations:
The function name is specified with -xinline.
If you compile at -xO4 or higher, in which case inlining is automatic.
If you use the inline specifier or cross-file optimization.
For example, suppose library ABC has a default allocator function that can be used by library clients, and is also used internally in the library:
void* ABC_allocator(size_t size) { return malloc(size); }
If you build the library at -xO4 or higher, the compiler inlines calls to ABC_allocator that occur in library components. If a library client wants to replace ABC_allocator with a customized version, the replacement will not occur in library components that called ABC_allocator. The final program will include different versions of the function.
Library functions declared with the __hidden or __symbolic specifiers can be generated inline when building the library. These specifiers are not supposed to be overridden by clients. See 4.1 Linker Scoping.
Library functions declared with the __global specifier, should not be declared inline, and should be protected from inlining by use of the -xinline compiler option.
-xinline, -xO
Causes libm to return IEEE 754 values for math routines in exceptional cases.
The default behavior of libm is XPG-compliant.
Numerical Computation Guide
Inlines selected libm math library routines for optimization.
Note - This option does not affect C++ inline functions.
This option selects inline templates for libm routines that produce the fastest executables for the floating-point option and platform currently being used.
This option is implied by the –fast option.
-fast, Numerical Computation Guide
Uses a library of optimized math routines. You must use default rounding mode by specifying -fround=nearest when you use this option.
This option uses a math routine library optimized for performance and usually generates faster code. The results might be slightly different from those produced by the normal math library; if so, they usually differ in the last bit.
The order on the command line for this library option is not significant.
This option is implied by the –fast option.
–fast, –xnolibmopt, -fround
Deprecated, do not use. Specify -library=sunperf instead. See A.2.49 -library=l[,l...] for more information.
This option is silently ignored by the compiler.
(SPARC only) Instructs the compiler to perform link-time optimization on the resulting executable or dynamic library over and above any optimizations in the object files. These optimizations are performed at link time by analyzing the object binary code. The object files are not rewritten but the resulting executable code may differ from the original object codes.
You must use -xlinkopt on at least some of the compilation commands for -xlinkopt to be useful at link time. The optimizer can still perform some limited optimizations on object binaries that are not compiled with -xlinkopt.
-xlinkopt optimizes code coming from static libraries that appear on the compiler command line, but it skips and does not optimize code coming from shared (dynamic) libraries that appear on the command line. You can also use -xlinkopt when you build shared libraries (compiling with -G).
level sets the level of optimizations performed, and must be 0, 1, or 2. The optimization levels are listed in the following table.:
Table A-37 The -xlinkopt Values
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If you compile in separate steps, -xlinkopt must appear on both compile and link steps:
example% cc -c -xlinkopt a.c b.c example% cc -o myprog -xlinkopt=2 a.o
Note that the level parameter is used only when the compiler is linking. In the example, the link optimizer level is 2 even though the object binaries are compiled with an implied level of 1.
Specifying -xlinkopt without a level parameter implies -xlinkopt=1.
This option is most effective when you use it to compile the whole program, and with profile feedback. Profiling reveals the most and least used parts of the code, and directs the optimizer to focus its effort accordingly. This is particularly important with large applications where optimal placement of code performed at link time can reduce instruction cache misses. This option is typically used as follows:
example% cc -o progt -xO5 -xprofile=collect:prog file.c example% progt example% cc -o prog -xO5 -xprofile=use:prog -xlinkopt file.c
For details on using profile feedback, see A.2.164 -xprofile=p.
Do not use the -zcombreloc linker option when you compile with -xlinkopt.
Note that compiling with this option increases link time slightly. Object file sizes also increase, but the size of the executable remains the same. Compiling with -xlinkopt and -g increases the size of the executable by including debugging information.
This option shows which loops are parallelized and is normally for use with the -xautopar option.
Runs only the C++ preprocessor on the named C++ programs, requesting that the preprocessor generate makefile dependencies and send the result to the standard output. See the make(1) man page for details about make files and dependencies.
However, -xM only reports dependencies of the included headers and not the associated template definition files. You can use the .KEEP_STATE feature in your makefile to generate all the dependencies in the .make.state file which the make utility creates.
The following example:
#include <unistd.h>
void main(void)
{}
generates this output:
e.o: e.c e.o: /usr/include/unistd.h e.o: /usr/include/sys/types.h e.o: /usr/include/sys/machtypes.h e.o: /usr/include/sys/select.h e.o: /usr/include/sys/time.h e.o: /usr/include/sys/types.h e.o: /usr/include/sys/time.h e.o: /usr/include/sys/unistd.h
If you specify -xM and -xMF, the compiler writes all makefile dependency information to the file specified with -xMF. This file is overwritten each time the preprocessor writes to it.
The make(1S) man page for details about makefiles and dependencies.
Generates makefile dependencies like –xM except that it does not report dependencies for the /usr/include header files and it does not report dependencies for compiler-supplied header files.
If you specify -xM1 and -xMF, the compiler writes all makefile dependency information to the file specified with -xMF. This file is overwritten each time the preprocessor writes to it.
Generates makefile dependencies like -xM but compilation continues. -xMD generates an output file for the makefile-dependency information derived from the -o output filename, if specified, or the input source filename, replacing (or adding) the filename suffix with .d . If you specify -xMD and -xMF, the preprocessor writes all makefile-dependency information to the file specified with -xMF. Compiling with -xMD -xMF or -xMD -o filename with more than one source file is not allowed and generates an error. The dependency file is overwritten if it already exists.
Use this option to specify a file for the makefile-dependency output. You cannot specify individual filenames for multiple input files with -xMF on one command line. Compiling with -xMD -xMF or -xMMD -xMF with more than one source file is not allowed and generates an error. The dependency file is overwritten if it already exists.
Use this option to generate makefile dependencies excluding system header files. This option provides the same functionality as -xM1, but compilation continues. -xMMD generates an output file for the makefile-dependency information derived from the -o output filename, if specified, or the input source filename, replacing (or adding) the filename suffix with .d . If you specify -xMF, the compiler uses the filename you provide instead. Compiling with -xMMD -xMF or -xMMD -o filename with more than one source file is not allowed and generates an error. The dependency file is overwritten if it already exists.
(SPARC only) Merges the data segment with the text segment.
The data in the object file is read-only and is shared between processes unless you link with ld -N.
The three options -xMerge -ztext -xprofile=collect should not be used together. While -xMerge forces statically initialized data into read-only storage, -ztext prohibits position-dependent symbol relocations in read-only storage, and -xprofile=collect generates statically initialized, position-dependent symbol relocations in writable storage.
ld(1) man page
This option limits the level of pragma opt to the level specified. v is one of off, 1, 2, 3, 4, 5. The default value is -xmaxopt=off which causes pragma opt to be ignored. The default when specifying -xmaxopt without supplying an argument is -xmaxopt=5.
If you specify both -xO and -xmaxopt, the optimization level set with -xO must not exceed the -xmaxopt value.
(SPARC only) Use the -xmemalign option to control the assumptions the compiler makes about the alignment of data. By controlling the code generated for potentially misaligned memory accesses and by controlling program behavior in the event of a misaligned access, you can more easily port your code to SPARC.
Specify the maximum assumed memory alignment and behavior of misaligned data accesses. You must profide a value for both a (alignment) and b (behavior). a specifies the maximum assumed memory alignment and b specifies the behavior for misaligned memory accesses.
For memory accesses where the alignment is determinable at compile time, the compiler generates the appropriate load/store instruction sequence for that alignment of data.
For memory accesses where the alignment cannot be determined at compile time, the compiler must assume an alignment to generate the needed load/store sequence.
If actual data alignment at runtime is less than the specified alignment, the misaligned access attempt (a memory read or write) generates a trap. The two possible responses to the trap are:
The OS converts the trap to a SIGBUS signal. If the program does not catch the signal, the program aborts. Even if the program catches the signal, the misaligned access attempt will not have succeeded.
The OS handles the trap by interpreting the misaligned access and returning control to the program as if the access had succeeded normally.
The following lists the alignment and behavior values for -xmemalign
Values for a:
Assume at most 1–byte alignment.
Assume at most 2–byte alignment.
Assume at most 4–byte alignment.
Assume at most 8–byte alignment.
Assume at most 16–byte alignment.
Values for b:
Interpret access and continue execution.
Raise signal SIGBUS
For 64–bit SPARC architectures: Raise signal SIGBUS for alignments less or equal to 4. Otherwise interpret access and continue execution.
For all other architectures, the flag is equivalent to i.
You must specify -xmemalign whenever you want to link to an object file that was compiled with the value of b set to either i or f. For a complete list of all compiler options that must be specified at both compile time and at link time, see 3.3.3 Compile-Time and Link-Time Options.
The following default values only apply when no -xmemalign option is present:
-xmemalign=8i for all 32–bit SPARC architectures (-m32)
-xmemalign=8s for all 64–bit SPARC architectures (-m64)
The following default value when the -xmemalign option is present but no value is given is:
-xmemalign=1i for all architectures.
The following shows how you can use -xmemalign to handle different alignment situations.
All memory accesses are misaligned so trap handling is too slow.
Occasional, intentional, misaligned accesses can occur in code that is otherwise correct.
No misaligned accesses occur in the program.
You want to check for possible odd-byte accesses.
You want to check for possible odd-byte access and you want the program to work.
(x86 only) The -xmodel option enables the compiler to modify the form of 64-bit objects for the Oracle Solaris x86 platforms and should be specified only for the compilation of such objects.
This option is valid only when -m64 is also specified on 64–bit enabled x64 processors.
The following table lists the possible values for a.
Table A-38 The -xmodel Flags
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This option is not cumulative so the compiler sets the model value according to the right-most instance of -xmodel on the command-line.
If you do not specify -xmodel, the compiler assumes -xmodel=small. Specifying -xmodel without an argument is an error.
You do not need to compile all translation units with this option. You can compile select files as long as you ensure the object you are accessing is within reach.
Be aware that not all Linux system support the medium model.
Disables linking with default system libraries.
Normally (without this option), the C++ compiler links with several system support libraries to support C++ programs. With this option, the -llib options to link the default system support libraries are not passed to ld.
Normally, the compiler links with the system support libraries in the following order:
With default —compat=5, the libraries are:
-lCstd -lCrun -lm -lc
For —compat=g on Linux, the libraries are:
—lstdc++ —lCrunG3 —lm —lc
For —compat=g on Oracle x86, the libraries are:
—lstdc++ —lgcc_s —lCrunG3 —lm —lc
The order of the -l options is significant. The -lm option must appear before -lc.
Note - If the -mt compiler option is specified, the compiler normally links with -lthread just before it links with -lm.
To determine which system support libraries will be linked by default, compile with the -dryrun option. For example, the output from the following command:
example% CC foo.cc -m64 -dryrun
shows the following in the output:
-lCstd -lCrun -lm -lc
For minimal compilation to meet the C application binary interface (that is, a C++ program with only C support required), use the following command:
example% CC -xnolib test.cc –lc
To link libm statically into a single-threaded application with the generic architecture instruction set, use the following command:
example% CC -xnolib test.cc -lCstd -lCrun -Bstatic -lm -Bdynamic -lc
If you specify– xnolib, you must manually link all required system support libraries in the given order. You must link the system support libraries last.
If -xnolib is specified, -library is ignored.
Many C++ language features require the use of libCrun (standard mode).
This set of system support libraries is not stable and might change from release to release.
–library, –staticlib, –l
Cancels –xlibmil on the command line.
Use this option with –fast to override linking with the optimized math library.
Does not use the math routine library.
Use this option after the –fast option on the command line, as in this example:
example% CC –fast –xnolibmopt
Same as A.2.60 -norunpath
Specifies optimization level; note the uppercase letter O followed by the digit 1, 2, 3, 4, or 5. In general, program execution speed depends on the level of optimization. The higher the level of optimization, the better the runtime performance. However, higher optimization levels can result in increased compilation time and larger executable files.
In a few cases, –xO2 might perform better than the others, and –xO3 might outperform –xO4. Try compiling with each level to see if you have one of these rare cases.
If the optimizer runs out of memory, it tries to recover by retrying the current procedure at a lower level of optimization. The optimizer resumes subsequent procedures at the original level specified in the -xOlevel option.
The following sections describe how the five -xOlevel optimization levels operate on the SPARC platform and the x86 platform.
On the SPARC Platform:
–xO1 does only the minimum amount of optimization (peephole), which is post-pass, assembly-level optimization. Do not use -xO1 unless using -xO2 or -xO3 results in excessive compilation time, or you are running out of swap space.
–xO2 does basic local and global optimization, which includes:
Induction-variable elimination
Local and global common-subexpression elimination
Algebraic simplification
Copy propagation
Constant propagation
Loop-invariant optimization
Register allocation
Basic block merging
Tail recursion elimination
Dead-code elimination
Tail-call elimination
Complicated expression expansion
This level does not optimize references or definitions for external or indirect variables.
–xO3, in addition to optimizations performed at the –xO2 level, also optimizes references and definitions for external variables. This level does not trace the effects of pointer assignments. When compiling either device drivers that are not properly protected by volatile or programs that modify external variables from within signal handlers, use -xO2. In general, this level results in increased code size unless combined with the -xspace option.
–xO4 does automatic inlining of functions contained in the same file in addition to performing –xO3 optimizations. This automatic inlining usually improves execution speed but sometimes makes it worse. In general, this level results in increased code size unless combined with the -xspace option.
–xO5 generates the highest level of optimization. It is suitable only for the small fraction of a program that uses the largest fraction of computer time. This level uses optimization algorithms that take more compilation time or that do not have as high a certainty of improving execution time. Optimization at this level is more likely to improve performance if it is done with profile feedback. See A.2.164 -xprofile=p.
On the x86 Platform:
–xO1 does basic optimization. This includes algebraic simplification, register allocation, basic block merging, dead code and store elimination, and peephole optimization.
–xO2 performs local common subexpression elimination, local copy and constant propagation, and tail recursion elimination, as well as the optimization done by level 1.
–xO3 performs global common subexpression elimination, global copy and constant propagation, loop strength reduction, induction variable elimination, and loop-variant optimization, as well as the optimization done by level 2.
–xO4 does automatic inlining of functions contained in the same file as well as the optimization done by level 3. This automatic inlining usually improves execution speed but sometimes makes it worse. This level also frees the frame pointer registration (ebp) for general purpose use. In general, this level results in increased code size.
–xO5 generates the highest level of optimization. It uses optimization algorithms that take more compilation time or that do not have as high a certainty of improving execution time.
If you use -g or -g0 and the optimization level is -xO3 or lower, the compiler provides best-effort symbolic information with almost full optimization.
If you use -g or -g0 and the optimization level is -xO4 or higher, the compiler provides best-effort symbolic information with full optimization.
Debugging with -g does not suppress –xOlevel, but –xOlevel limits –g in certain ways. For example, the –xOlevel options reduce the utility of debugging so that you cannot display variables from dbx, but you can still use the dbx where command to get a symbolic traceback. For more information, see Debugging a Program With dbx.
The -xipo option is effective only if it is used with -xO4 or -xO5.
The -xinline option has no effect for optimization levels below -xO3. At -xO4, the optimizer decides which functions should be inlined, and does so regardless of whether you specify the -xinline option. At -xO4, the compiler also attempts to determine which functions will improve performance if they are inlined. If you force the inlining of a function with -xinline, you might actually diminish performance.
The default is no optimization. However, this is only possible if you do not specify an optimization level. If you specify an optimization level, there is no option for turning optimization off.
If you are trying to avoid setting an optimization level, be sure not to specify any option that implies an optimization level. For example, -fast is a macro option that sets optimization at -xO5. All other options that imply an optimization level issue a warning message that optimization has been set. The only way to compile without any optimization is to delete all options from the command line or make file that specify an optimization level.
If you optimize at –xO3 or –xO4 with very large procedures (thousands of lines of code in a single procedure), the optimizer might require an unreasonable amount of memory. In such cases, machine performance can be degraded.
To prevent this degradation from taking place, use the limit command to limit the amount of virtual memory available to a single process. See the csh(1) man page. For example, to limit virtual memory to 4 gigabytes:
example% limit datasize 4G
This command causes the optimizer to try to recover if it reaches 4 gigabytes of data space.
The limit cannot be greater than the total available swap space of the machine, and should be small enough to permit normal use of the machine while a large compilation is in progress.
The best setting for data size depends on the degree of optimization requested, the amount of real memory, and virtual memory available.
To find the actual swap space, type swap– l
To find the actual real memory, type dmesg | grep mem
-xldscope –fast, –xprofile=p, csh(1) man page
Use the -xopenmp option to enable explicit parallelization with OpenMP directives.
The following table lists the values for i.
Table A-39 -xopenmp Values
|
If you do not specify -xopenmp, the compiler default is -xopenmp=none.
If you specify -xopenmp without an argument, the compiler default is -xopenmp=parallel.
If you are debugging an OpenMP program with dbx, compile with -g and -xopenmp=noopt so you can breakpoint within parallel regions and display the contents of variables.
Use the OMP_NUM_THREADS environment variable to specify the number of threads to use when running an OpenMP program. If OMP_NUM_THREADS is not set, the default number of threads used is 2. To use more threads, set OMP_NUM_THREADS to a higher value. Set OMP_NUM_THREADS to 1 to run with just one thread. In general, set OMP_NUM_THREADS to the available number of virtual processors on the running system, which can be determined by using the Oracle Solaris psrinfo(1) command. See the Oracle Solaris Studio OpenMP API User's Guide for more information.
To enable nested parallelism, you must set the OMP_NESTED environment variable to TRUE. Nested parallelism is disabled by default. See the Oracle Solaris Studio OpenMP API User's Guide for details.
The default for -xopenmp might change in future releases. You can avoid warning messages by explicitly specifying an appropriate optimization.
If you compile and link in separate steps, specify -xopenmp in both the compilation step and the link step. This is important if you are building a shared object. The compiler which was used to compile the executable must not be any older than the compiler that built the .so with -xopenmp. This is especially important when you compile libraries that contain OpenMP directives. See 3.3.3 Compile-Time and Link-Time Options for a complete list of options that must be specified at both compile time and link time.
Make sure that the latest patch of the OpenMP runtime library, libmtsk.so, is installed on the system for best performance.
For a complete summary of the OpenMP Fortran 95, C, and C++ application program interface (API) for building multiprocessing applications, see the Oracle Solaris Studio OpenMP API User’s Guide.
Sets the preferred page size for the stack and the heap.
The following values are valid for SPARC: 4k, 8K, 64K, 512K, 2M, 4M, 32M, 256M, 2G, 16G, or default.
The following values are valid on x86/x64: 4K, 2M. 4M, 1G, or default.
You must specify a valid page size for the target platform. If you do not specify a valid page size, the request is silently ignored at runtime.
Use the getpagesize(3C) command on the Oracle Solaris operating system to determine the number of bytes in a page. The Solaris operating system offers no guarantee that the page size request will be honored. You can use pmap(1) or meminfo(2) to determine the page size of the target platform.
Note - Compiling with this option has the same effect as setting the LD_PRELOAD environment variable to mpss.so.1 with the equivalent options, or running the Oracle Solaris command ppgsz(1) with the equivalent options before running the program. See the Oracle Solaris man pages for details.
If you specify -xpagesize=default, the Oracle Solaris operating system sets the page size.
This option is a macro for -xpagesize_heap and -xpagesize_stack. These two options accept the same arguments as -xpagesize: 4k, 8K, 64K, 512K, 2M, 4M, 32M, 256M, 2G, 16G, or default. You can set them both with the same value by specifying -xpagesize or you can specify them individually with different values.
The -xpagesize option has no effect unless you use it at compile time and at link time. See 3.3.3 Compile-Time and Link-Time Options for a complete list of options that must be specified at both compile time and link time.
Set the page size in memory for the heap.
n can be 4k, 8K, 64K, 512K, 2M, 4M, 32M, 256M, 2G, 16G, or default. You must specify a valid page size for the target platform. If you do not specify a valid page size, the request is silently ignored at runtime.
Use the getpagesize(3C) command on the Oracle Solaris operating system to determine the number of bytes in a page. The Solaris operating system offers no guarantee that the page size request will be honored. You can use pmap(1) or meminfo(2) to determine the page size of the target platform.
Note - Compiling with this option has the same effect as setting the LD_PRELOAD environment variable to mpss.so.1 with the equivalent options, or running the Oracle Solaris command ppgsz(1) with the equivalent options before running the program. See the Oracle Solaris man pages for details.
If you specify -xpagesize_heap=default, the Oracle Solaris operating system sets the page size.
The -xpagesize_heap option has no effect unless you use it at compile time and at link time.
Set the page size in memory for the stack.
n can be 4k, 8K, 64K, 512K, 2M, 4M, 32M, 256M, 2G, 16G, or default. You must specify a valid page size for the target platform. If you do not specify a valid page size, the request is silently ignored at runtime.
Use the getpagesize(3C) command on the Oracle Solaris operating system to determine the number of bytes in a page. The Oracle Solaris operating system offers no guarantee that the page size request will be honored. You can use pmap(1) or meminfo(2) to determine the page size of the target platform.
Note - Compiling with this option has the same effect as setting the LD_PRELOAD environment variable to mpss.so.1 with the equivalent options, or running the Oracle Solaris command ppgsz(1) with the equivalent options before running the program. See the Oracle Solaris man pages for details.
If you specify -xpagesize_stack=default, the Oracle Solaris operating system sets the page size.
The -xpagesize_stack option has no effect unless you use it at compile time and at link time.
This compiler option activates the precompiled-header feature. The precompiled-header feature might reduce compile time for applications whose source files share a common set of include files containing a large amount of source code. The compiler collects information about a sequence of header files from one source file, and then uses that information when recompiling that source file, and when compiling other source files that have the same sequence of headers. The information that the compiler collects is stored in a precompiled-header file. You can take advantage of this feature through the -xpch and -xpchstop options in combination with the #pragma hdrstop directive.
When you specify -xpch=v, v can be collect:pch-filename or use:pch-filename. The first time you use -xpch, you must specify the collect mode. The compilation command that specifies -xpch=collect must only specify one source file. In the following example, the -xpch option creates a precompiled-header file called myheader.Cpch based on the source file a.cc:
CC -xpch=collect:myheader a.cc
A valid precompiled-header filename always has the suffix .Cpch. When you specify pch-filename, you can add the suffix or let the compiler add it for you. For example, if you specify cc -xpch=collect:foo a.cc, the precompiled-header file is called foo.Cpch.
When you create a precompiled-header file, pick a source file that contains the common sequence of include files across all the source files with which the precompiled-header file is to be used. The common sequence of include files must be identical across these source files. Remember, only one source filename value is legal in collect mode. For example, CC -xpch=collect:foo bar.cc is valid, whereas CC -xpch=collect:foo bar.cc foobar.cc is invalid because it specifies two source files.
Specify -xpch=use:pch-filename to use a precompiled-header file. You can specify any number of source files with the same sequence of include files as the source file that was used to create the precompiled-header file. For example, your command in use mode could look like this: CC -xpch=use:foo.Cpch foo.c bar.cc foobar.cc.
You should only use an existing precompiled-header file if the following situations are true. If any are not true, you should recreate the precompiled-header file:
The compiler that you are using to access the precompiled-header file is the same as the compiler that created the precompiled-header file. A precompiled-header file created by one version of the compiler might not be usable by another version of the compiler, including differences caused by installed patches.
Except for the -xpch option, the compiler options you specify with -xpch=use must match the options that were specified when the precompiled-header file was created.
The set of included headers you specify with -xpch=use is identical to the set of headers that were specified when the precompile header was created.
The contents of the included headers that you specify with -xpch=use is identical to the contents of the included headers that were specified when the precompiled header was created.
The current directory (that is, the directory in which the compilation is occurring and attempting to use a given precompiled-header file) is the same as the directory in which the precompiled-header file was created.
The initial sequence of preprocessing directives, including #include directives, in the file you specified with -xpch=collect are the same as the sequence of preprocessing directives in the files you specify with -xpch=use.
In order to share a precompiled-header file across multiple source files, those source files must share a common set of include files as their initial sequence of tokens. This initial sequence of tokens is known as the viable prefix. The viable prefix must be interpreted consistently across all the source files that use the same precompiled-header file.
The viable prefix of a source file can only be comprised of comments and any of the following preprocessor directives:
#include #if/ifdef/ifndef/else/elif/endif #define/undef #ident (if identical, passed through as is) #pragma (if identical)
Any of these directives may reference macros. The #else, #elif, and #endif directives must match within the viable prefix.
Within the viable prefix of each file that shares a precompiled-header file, each corresponding #define and #undef directive must reference the same symbol. In the case of #define, each one must reference the same value. Their order of appearance within each viable prefix must be the same as well. Each corresponding pragma must also be the same and appear in the same order across all the files sharing a precompiled header.
A header file that is incorporated into a precompiled-header file must not violate the following constraints. The results of compiling a program that violates any of these constraints is undefined.
The header file must not contain function and variable definitions.
The header file must not use __DATE__ and __TIME__. Use of these preprocessor macros can generate unpredictable results.
The header file must not contain #pragma hdrstop.
The header file must not use __LINE__ and __FILE__ in the viable prefix. You can use __LINE__ and __FILE__ in included headers.
This section describes possible approaches to modifying your makefiles in order to incorporate -xpch into your builds.
You can use the implicit make rules by using an auxiliary CCFLAGS variable and the KEEP_STATE facility of both make and dmake. The precompiled header is produced as a separate independent step.
.KEEP_STATE:
CCFLAGS_AUX = -O etc
CCFLAGS = -xpch=use:shared $(CCFLAGS_AUX)
shared.Cpch: foo.cc
$(CCC) -xpch=collect:shared $(CCFLAGS_AUX) foo.cc
a.out: foo.o ping.o pong.o
$(CCC) foo.o ping.o pong.o
You can also define your own compilation rule instead of trying to use an auxiliary CCFLAGS.
.KEEP_STATE:
.SUFFIXES: .o .cc
%.o:%.cc shared.Cpch
$(CCC) -xpch=use:shared $(CCFLAGS) -c $<
shared.Cpch: foo.cc
$(CCC) -xpch=collect:shared $(CCFLAGS) foo.cc -xe
a.out: foo.o ping.o pong.o
$(CCC) foo.o ping.o pong.o
You can produce the precompiled header as a side effect of regular compilation and without using KEEP_STATE, but this approach requires explicit compilation commands.
shared.Cpch + foo.o: foo.cc bar.h
$(CCC) -xpch=collect:shared foo.cc $(CCFLAGS) -c
ping.o: ping.cc shared.Cpch bar.h
$(CCC) -xpch=use:shared ping.cc $(CCFLAGS) -c
pong.o: pong.cc shared.Cpch bar.h
$(CCC) -xpch=use:shared pong.cc $(CCFLAGS) -c
a.out: foo.o ping.o pong.o
$(CCC) foo.o ping.o pong.o
Use the -xpchstop=file option to specify the last include file to be considered in creating the precompiled header file with the -xpch option. Using -xpchstop on the command line is equivalent to placing a hdrstop pragma after the first include-directive that references file in each of the source files that you specify with the cc command.
In the following example, the -xpchstop option specifies that the viable prefix for the precompiled header file ends with the include of projectheader.h. Therefore, privateheader.h is not a part of the viable prefix.
example% cat a.cc
#include <stdio.h>
#include <strings.h>
#include "projectheader.h"
#include "privateheader.h"
.
.
.
example% CC -xpch=collect:foo.Cpch a.cc -xpchstop=projectheader.h -c
-xpch, pragma hdrstop
(Solaris only) Generates a Portable Executable Code (PEC) binary. This option puts the program intermediate representations in the object file and the binary. This binary may be used later for tuning and troubleshooting.
A binary that is built with -xpecis usually five to ten times larger than if it is built without -xpec.
If you do not specify -xpec, the compiler sets it to -xpec=no. If you specify -xpec, but do not supply a flag, the compiler sets it to -xpec=yes.
Compiles for profiling with the gprof profiler.
The-xpg option compiles self-profiling code to collect data for profiling with gprof. This option invokes a runtime recording mechanism that produces a gmon.out file when the program normally terminates.
Note - -xprofile does not benefit if you specify -xpg. The two do not prepare or use data provided by the other.
Profiles are generated by using prof(1) or gprof(1) on 64–bit Solaris platforms or just gprof on 32–bit Solaris platforms and include approximate user CPU times. These times are derived from PC sample data for routines in the main executable and routines in shared libraries specified as linker arguments when the executable is linked. Other shared libraries (libraries opened after process startup using dlopen(3DL)) are not profiled.
On 32–bit Solaris systems, profiles generated using prof(1) are limited to routines in the executable. 32–bit shared libraries can be profiled by linking the executable with -xpg and using gprof(1).
On x86 systems, -xpg is incompatible with -xregs=frameptr, and these two options should not be used together. Note also that -xregs=frameptr is included in -fast.
The Oracle Solaris 10 software does not include system libraries compiled with -p. As a result, profiles collected on Solaris 10 platforms do not include call counts for system library routines.
If you compile and link separately and you compile with –xpg, be sure to link with –xpg. See 3.3.3 Compile-Time and Link-Time Options for a complete list of options that must be specified at both compile time and link time.
Binaries compiled with -xpg for gprof profiling should not be used with binopt(1), as they are incompatible and can result in internal errors.
–xprofile=p, the analyzer(1) man page, and the Performance Analyzer manual
Use this option to help you debug code you are porting to a 64-bit environment. Specifically, this option warns against problems such as truncation of types (including pointers), sign extension, and changes to bit-packing that are common when code is ported from a 32-bit architecture such as V8 to a 64-bit architecture such as V9.
This option has no effect unless you are also compiling in 64–bit mode, —m64.
The following table lists the valid values for v.
Table A-40 -xport64 Values
|
If you do not specify -xport64, the default is -xport64=no. If you specify -xport64 but do not specify a flag, the default is -xport64=full.
This section provides examples of code that can cause truncation of type, sign extension, and changes to bit-packing.
When you port to a 64-bit architecture such as SPARC V9, your data may be truncated. The truncation could happen implicitly, by assignment, at initialization, or by an explicit cast. The difference of two pointers is the typedef ptrdiff_t, which is a 32-bit integer type in 32-bit mode, and a 64-bit integer type in 64-bit mode. The truncation of a long to a smaller size integral type generates a warning as in the following example.
example% cat test1.c int x[10]; int diff = &x[10] - &x[5]; //warn example% CC -c -m64 -Qoption ccfe -xport64=full test1.c "test1.c", line 3: Warning: Conversion of 64-bit type value to "int" causes truncation. 1 Warning(s) detected. example%
Use -xport64=implicit to disable truncation warnings in 64–bit compilation mode when an explicit cast is the cause of data truncation.
example% CC -c -m64 -Qoption ccfe -xport64=implicit test1.c "test1.c", line 3: Warning: Conversion of 64-bit type value to "int" causes truncation. 1 Warning(s) detected. example%
Another common issue that arises from porting to a 64-bit architecture is the truncation of a pointer. This is always an error in C++. An operation such as casting a pointer to an int which causes such a truncation results in an error diagnostic in 64–bit SPARC architectures when you specify -xport64.
example% cat test2.c
char* p;
int main() {
p =(char*) (((unsigned int)p) & 0xFF); // -m64 error
return 0;
}
example% CC -c -m64 -Qoption ccfe -xport64=full test2.c
"test2.c", line 3: Error: Cannot cast from char* to unsigned.
1 Error(s) detected.
example%
You can also use the -xport64 option to check for situations in which the normal ISO C value-preserving rules allow for the extension of the sign of a signed-integral value in an expression of unsigned-integral type. Such sign extensions can cause subtle run-time bugs.
example% cat test3.c
int i= -1;
void promo(unsigned long l) {}
int main() {
unsigned long l;
l = i; // warn
promo(i); // warn
}
example% CC -c -m64 -Qoption ccfe -xport64=full test3.c
"test3.c", line 6: Warning: Sign extension from "int" to 64-bit integer.
"test3.c", line 7: Warning: Sign extension from "int" to 64-bit integer.
2 Warning(s) detected.
Use -xport64 to generate warnings against long bitfields. In the presence of such bitfields, packing of the bitfields might drastically change. Any program which relies on assumptions regarding the way bitfields are packed needs to be reviewed before a successful port can take place to a 64-bit architecture.
example% cat test4.c
#include <stdio.h>
union U {
struct S {
unsigned long b1:20;
unsigned long b2:20;
} s;
long buf[2];
} u;
int main() {
u.s.b1 = 0XFFFFF;
u.s.b2 = 0XFFFFF;
printf(" u.buf[0] = %lx u.buf[1] = %lx\n", u.buf[0], u.buf[1]);
return 0;
}
example%
Output on 64–bit SPARC systems (-m64):
example% u.buf[0] = ffffffffff000000 u.buf[1] = 0
Note that warnings are generated only when you compile in 64-bit mode using -m64.
Enable prefetch instructions on those architectures that support prefetch.
Explicit prefetching should only be used under special circumstances that are supported by measurements.
The following table lists the possible values of a .
Table A-41 -xprefetch Values
|
With -xprefetch and -xprefetch=auto the compiler is free to insert prefetch instructions into the code it generates. This may result in a performance improvement on architectures that support prefetch.
If you are running computationally intensive codes on large multiprocessors, using -xprefetch=latx:factor could improve performance. This option instructs the code generator to adjust the default latency time between a prefetch and its associated load or store by the specified factor.
The prefetch latency is the hardware delay between the execution of a prefetch instruction and the time the data being prefetched is available in the cache. The compiler assumes a prefetch latency value when determining how far apart to place a prefetch instruction and the load or store instruction that uses the prefetched data.
Note - The assumed latency between a prefetch and a load may not be the same as the assumed latency between a prefetch and a store.
The compiler tunes the prefetch mechanism for optimal performance across a wide range of machines and applications. This tuning may not always be optimal. For memory-intensive applications, especially applications intended to run on large multiprocessors, you may be able to obtain better performance by increasing the prefetch latency values. To increase the values, use a factor that is greater than 1 (one). A value between .5 and 2.0 will most likely provide the maximum performance.
For applications with data sets that reside entirely within the external cache, you may be able to obtain better performance by decreasing the prefetch latency values. To decrease the values, use a factor that is less than 1 (one).
To use the -xprefetch=latx:factor option, start with a factor value near 1.0 and run performance tests against the application. Then increase or decrease the factor, as appropriate, and run the performance tests again. Continue adjusting the factor and running the performance tests until you achieve optimum performance. When you increase or decrease the factor in small steps, you will see no performance difference for a few steps, then a sudden difference, then it will level off again.
The default is -xprefetch=auto,explicit. This default adversely affects applications that have essentially non-linear memory access patterns. Specify -xprefetch=no%auto,no%explicit to override the default.
The default of auto is assumed unless explicitly overridden with an argument of no%auto or an argument of no. For example, -xprefetch=explicit is the same as -xprefetch=explicit,auto.
The default of explicit is assumed unless explicitly overridden with an argument of no%explicit or an argument of no. For example, -xprefetch=auto is the same as -xprefetch=auto,explicit.
If only -xprefetch is specified, -xprefetch=auto,explicit is assumed.
If automatic prefetching is enabled, but a latency factor is not specified, then -xprefetch=latx:1.0 is assumed.
This option accumulates instead of overrides.
The sun_prefetch.h header file provides the macros for specifying explicit prefetch instructions. The prefetches will be approximately at the place in the executable that corresponds to where the macros appear.
To use the explicit prefetch instructions, you must be on the correct architecture, include sun_prefetch.h, and either exclude -xprefetch from the compiler command or use -xprefetch, -xprefetch=auto,explicit or -xprefetch=explicit.
If you call the macros and include the sun_prefetch.h header file but specify -xprefetch=no%explicit, the explicit prefetches will not appear in your executable.
The use of latx:factor is valid only when automatic prefetching is enabled. latx:factor is ignored unless you use it in conjunction with -xprefetch=auto,latx:factor.
Explicit prefetching should be used only under special circumstances that are supported by measurements.
Because the compiler tunes the prefetch mechanism for optimal performance across a wide range of machines and applications, you should use -xprefetch=latx:factor only when the performance tests indicate there is a clear benefit. The assumed prefetch latencies might change from release to release. Therefore, retesting the effect of the latency factor on performance whenever switching to a different release is highly recommended.
Where a is [no%]indirect_array_access.
Use this option to determine whether the compiler generates indirect prefetches for the loops indicated by the option -xprefetch_level in the same fashion the prefetches for direct memory accesses are generated.
If you do not specify a setting for -xprefetch_auto_type, the compiler sets it to -xprefetch_auto_type=no%indirect_array_access.
Options such as -xdepend, -xrestrict, and -xalias_level can affect the aggressiveness of computing the indirect prefetch candidates and therefore the aggressiveness of the automatic indirect prefetch insertion due to better memory alias disambiguation information.
Use the -xprefetch_level=i option to control the aggressiveness of the automatic insertion of prefetch instructions as determined with -xprefetch=auto. The compiler becomes more aggressive, or, in other words, introduces more prefetches, with each higher level of -xprefetch_level.
The appropriate value for -xprefetch_level depends on the number of cache misses your application has. Higher -xprefetch_level values have the potential to improve the performance of applications with a high number of cache misses.
i must be one of 1, 2, or 3, as shown in the following table.
Table A-42 -xprefetch_level Values
|
The default is -xprefetch_level=1 when you specify -xprefetch=auto.
This option is effective only when it is compiled with -xprefetch=auto, with optimization level 3 or greater (-xO3), and on 64–bit SPARC platforms that support prefetch (-m64).
Collects data for a profile or uses a profile to optimize.
p must be collect[:profdir], use[:profdir], or tcov[:profdir].
This option causes execution frequency data to be collected and saved during execution, then the data can be used in subsequent runs to improve performance. Profile collection is safe for multithreaded applications. Profiling a program that does its own multitasking ( -mt ) produces accurate results. This option is only valid when you specify -xO2 or greater level of optimization. If compilation and linking are performed in separate steps, the same -xprofile option must appear on the link step as well as the compile step.
Collects and saves execution frequency for later use by the optimizer with -xprofile=use. The compiler generates code to measure statement execution-frequency.
-xMerge, -ztext, and -xprofile=collect should not be used together. While -xMerge forces statically initialized data into read-only storage, -ztext prohibits position-dependent symbol relocations in read-only storage, and -xprofile=collect generates statically initialized, position-dependent symbol relocations in writable storage.
The profile directory name profdir, if specified, is the pathname of the directory where profile data are to be stored when a program or shared library containing the profiled object code is executed. If the profdir pathname is not absolute, it is interpreted relative to the current working directory when the program is compiled with the option -xprofile=use:profdir.
If no profile directory name is specified with —xprofile=collect:prof_dir or —xprofile=tcov:prof_dir, profile data are stored at run time in a directory named program.profile where program is the basename of the profiled process's main program. In this case, the environment variables SUN_PROFDATA and SUN_PROFDATA_DIR can be used to control where the profile data are stored at run time. If set, the profile data are written to the directory given by $SUN_PROFDATA_DIR/$SUN_PROFDATA. If a profile directory name is specified at compi lation time, SUN_PROFDATA_DIR and SUN_PROFDATA have no effect at run time. These environment variables similarly control the path and names of the profile data files written by tcov, as described in the tcov(1) man page.
If these environment variables are not set, the profile data is written to the directory profdir.profile in the current directory, where profdir is the name of the executable or the name specified in the -xprofile=collect:profdir flag. -xprofile does not append .profile to profdir if profdir already ends in .profile. If you run the program several times, the execution frequency data accumulates in the profdir.profile directory; that is output from prior executions is not lost.
If you are compiling and linking in separate steps, make sure that any object files compiled with -xprofile=collect are also linked with -xprofile=collect.
The following example collects and uses profile data in the directory myprof.profile located in the same directory where the program is built:
demo: CC -xprofile=collect:myprof.profile -xO5 prog.cc -o prog demo: ./prog demo: CC -xprofile=use:myprof.profile -xO5 prog.cc -o prog
The following example collects profile data in the directory /bench/myprof.profile and later uses the collected profile data in a feedback compilation at optimization level -xO5:
demo: CC -xprofile=collect:/bench/myprof.profile \ -xO5 prog.cc -o prog ...run prog from multiple locations.. demo: CC -xprofile=use:/bench/myprof.profile \ -xO5 prog.cc -o prog
Uses execution frequency data collected from code compiled with —xprofile=collect[:profdir] or —xprofile=tcov[:profdir] to optimize for the work performed when the profiled code was executed. profdir is the pathname of a directory containing profile data collected by running a program that was compiled with —xprofile=collect[:profdir] or —xprofile=tcov[:profdir].
To generate data that can be used by both tcov and —xprofile=use[:profdir], a profile directory must be specified at compilation time, using the option —xprofile=tcov[:profdir]. The same profile directory must be specified in both —xprofile=tcov:profdir and —xprofile=use:profdir. To minimize confusion, specify profdir as an absolute pathname.
The profdir pathname is optional. If profdir is not specified, the name of the executable binary is used. a.out is used if -o is not specified. The compiler looks for profdir.profile/feedback, or a.out.profile/feedback when profdir is not specified. For example:
demo: CC -xprofile=collect -o myexe prog.cc demo: CC -xprofile=use:myexe -xO5 -o myexe prog.cc
The program is optimized by using the execution frequency data previously generated and saved in the feedback files written by a previous execution of the program compiled with -xprofile=collect.
Except for the -xprofile option, the source files and other compiler options must be exactly the same as those used for the compilation that created the compiled program that generated the feedback file. The same version of the compiler must be used for both the collect build and the use build as well.
If compiled with -xprofile=collect:profdir, the same profile directory name profdir must be used in the optimizing compilation: -xprofile=use:profdir.
See also -xprofile_ircache for speeding up compilation between collect and use phases.
Instrument object files for basic block coverage analysis using tcov(1).
If the optional profdir argument is specified, the compiler will create a profile directory at the specified location The data stored in the profile directory can be used either by tcov(1) or by the compiler with -xprofile=use:profdir. If the optional profdir pathname is omitted, a profile directory will be created when the profiled program is executed. The data stored in the profile directory can only be used by tcov(1). The location of the profile directory can be controlled using environment variables SUN_PROFDATA and SUN_PROFDATA_DIR.
If the location specified by profdir is not an absolute pathname, it is interpreted at compilation time relative to the current working directory at the time of compilation. If profdir is specified for any object file, the same location must be specified for all object files in the same program. The directory whose location is specified by profdir must be accessible from all machines where the profiled program is to be executed. The profile directory should not be deleted until its contents are no longer needed, because data stored there by the compiler cannot be restored except by recompilation.
If object files for one or more programs are compiled with -xprofile=tcov:/test/profdata, a directory named /test/profdata.profile will be created by the compiler and used to store data describing the profiled object files. The same directory will also be used at execution time to store execution data associated with the profiled object files.
If a program named myprog is compiled with -xprofile=tcov and executed in the directory /home/joe, the directory /home/joe/myprog.profile will be created at runtime and used to store runtime profile data.
(SPARC only) Use -xprofile_ircache[=path] with -xprofile=collect|use to improve compilation time during the use phase by reusing compilation data saved from the collect phase.
With large programs, compilation time in the use phase can improve significantly because the intermediate data is saved. Note that the saved data could increase disk space requirements considerably.
When you use -xprofile_ircache[=path], path overrides the location where the cached files are saved. By default, these files are saved in the same directory as the object file. Specifying a path is useful when the collect and use phases happen in two different directories. The following example shows a typical sequence of commands:
example% CC -xO5 -xprofile=collect -xprofile_ircache t1.cc t2.cc example% a.out // run collects feedback data example% CC -xO5 -xprofile=use -xprofile_ircache t1.cc t2.cc
(SPARC only) Use the -xprofile_pathmap=collect-prefix:use-prefix option when you are also specifying the -xprofile=use command. Use -xprofile_pathmap when both of the following conditions are true and the compiler is unable to find profile data for an object file that is compiled with -xprofile=use.
You are compiling the object file with -xprofile=use in a directory that is different from the directory in which the object file was previously compiled with -xprofile=collect.
Your object files share a common basename in the profile but are distinguished from each other by their location in different directories.
The collect-prefix is the prefix of the UNIX path name of a directory tree in which object files were compiled using -xprofile=collect.
The use-prefix is the prefix of the UNIX path name of a directory tree in which object files are to be compiled using -xprofile=use.
If you specify multiple instances of -xprofile_pathmap, the compiler processes them in the order of their occurrence. Each use-prefix specified by an instance of -xprofile_pathmap is compared with the object file path name until either a matching use-prefix is identified or the last specified use-prefix is found not to match the object file path name.
Analyzes loops for reduction in automatic parallelization. This option is valid only if -xautopar is also specified. Otherwise the compiler issues a warning.
When reduction recognition is enabled, the compiler parallelizes reductions such as dot products, and maximum and minimum finding. These reductions yield different roundoffs from those obtained by unparallelized code.
Specifies the usage of registers for the generated code.
r is a comma-separated list that consists of one or more of the following suboptions: appl, float,frameptr.
Prefixing a suboption with no% disables that suboption. For example: -xregs=appl,no%float
Note that —xregs suboptions are restricted to specific hardware platforms.
Table A-43 -xregs Suboptions
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The SPARC default is -xregs=appl,float.
The x86 default is -xregs=no%frameptr.
On x86 systems, -xpg is incompatible with -xregs=frameptr, and these two options should not be used together. Note also that -xregs=frameptr is included in -fast.
Code intended for shared libraries that will link with applications should be compiled with -xregs=no%appl,float. At the very least, the shared library should explicitly document how it uses the application registers so that applications linking with those libraries are aware of these register assignments.
For example, an application using the registers in some global sense (such as using a register to point to some critical data structure) would need to know exactly how a library with code compiled without -xregs=no%appl is using the application registers in order to safely link with that library.
Treats pointer-valued function parameters as restricted pointers . f must be one of the values listed in the following table:
Table A-44 -xrestrict Values
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This command-line option can be used on its own, but it is best used with optimization.
For example, the following command treats all pointer parameters in the file prog.c as restricted pointers.
%CC -xO3 -xrestrict=%all prog.cc
The following command treats all pointer parameters in the function agc in the file prog.c as restricted pointers:
%CC -xO3 -xrestrict=agc prog.cc
Note that C99 standard for the C programming language introduced the restrict keyword, but the keyword is not part of the current C++ standard. Some compilers have a C++ language extension for the C99 restrict keyword, sometimes spelled __restrict or __restrict__. The Oracle Solaris Studio C++ compiler, however, does not currently have this extension. The -xrestrict option is a partial substitute for the restrict keyword in source code. (With the keyword, not all of the pointer arguments of a function need to be declared restrict.) The keyword primarily affects optimization opportunities, and limits the arguments that can be passed to a function. Removing all instances of restict or __restrict from source code does not affect the observable behavior of a program.
The default is %none; specifying -xrestrict is equivalent to specifying -xrestrict=%source.
In order for a compiler to effectively perform parallel execution of a loop, it needs to determine if certain lvalues designate distinct regions of storage. Aliases are lvalues whose regions of storage are not distinct. Determining if two pointers to objects are aliases is a difficult and time consuming process because it could require analysis of the entire program. Consider the function vsq() in the following exam ple:
extern "C"
void vsq(int n, double *a, double *b) {
int i;
for (i=0; i<n; i++) {
b[i] = a[i] * a[i];
}
}
The compiler can parallelize the execution of the different iterations of the loops if it knows that pointers a and b access different objects. If there is an overlap in objects accessed through pointers a and b then it would be unsafe for the compiler to execute the loops in parallel.
At compile time, the compiler does not know if the objects accessed by a and b overlap by simply analyzing the function vsq(). The compiler may need to analyze the whole program to get this information. You can specify that pointer-valued function parameters be treated as restricted pointers by using the following command line option: -xrestrict[=func1,...,funcn] If a function list is specified, pointer parameters in the specified functions are treated as restricted. Otherwise, all pointer parameters in the entire source file are treated as restricted (not recommended). For example, -xrestrict=vsq qualifies the pointers a and b given in the example of the function vsq().
Declaring the pointer arguments as restricted states that the pointers designate distinct objects. The compiler can assume that a and b point to distinct regions of storage. With this alias information, the compiler is able to parallelize the loop.
Make sure you use -xrestrict correctly. If pointers qualified as restricted pointers point to objects that are not distinct, the compiler can incorrectly parallelize loops resulting in undefined behavior. For example, assume that pointers a and b of function vsq() point to objects that overlap such that b[i] and a[i+1] are the same object. If a and b are not declared as restricted pointers the loops will be executed serially. If a and b are incorrectly qualified as restricted pointers, the compiler might parallelize the execution of the loops, which is not safe because b[i+1] should only be computed after b[i] is computed
Allows debugging by dbx without object (.o) files.
This option causes all the debug information to be copied into the executable. This option has little impact on dbx performance or the runtime performance of the program, but it does take more disk space.
This option has an effect only with -xdebugformat=stabs, where the default is not to copy debug data into the executable. With the default debug format -xdebugformat=dwarf, debug data is always copied into the executable, and there is no option to prevent the copying.
(SPARC only) Allows the compiler to assume that no memory protection violations occur.
This option allows the compiler to use the non-faulting load instruction in the SPARC V9 architecture.
This option takes effect only when used with optimization level -xO5 and one of the following -xarch values: sparc, sparcvis, sparcvis2, or sparcvis3 for both -m32 and -m64.
Because non-faulting loads do not cause a trap when a fault such as address misalignment or segmentation violation occurs, you should use this option only for programs in which such faults cannot occur. Because few programs incur memory-based traps, you can safely use this option for most programs. Do not use this option for programs that explicitly depend on memory-based traps to handle exceptional conditions.
SPARC: Does not allow optimizations that increase code size.
Specifies the target platform for instruction set and optimization.
The performance of some programs can benefit by providing the compiler with an accurate description of the target computer hardware. When program performance is critical, the proper specification of the target hardware could be very important. This is especially true when running on the newer SPARC processors. However, for most programs and older SPARC processors, the performance gain is negligible and a generic specification is sufficient.
The value of t must be one of the following: native, generic, native64, generic64, system-name.
Each specific value for -xtarget expands into a specific set of values for the -xarch, -xchip, and -xcache options. Use the -xdryrun option to determine the expansion of -xtarget=native on a running system.
For example, -xtarget=ultraT2 is equivalent to: -xarch=sparcvis2 -xchip=ultraT2 -xcache=8/16/4:4096/64/16.
Note - The expansion of -xtarget for a specific host platform might not expand to the same -xarch, -xchip, or -xcache settings as -xtarget=native when compiling on that platform.
This section provides descriptions of the —xtarget values by platform. The following table lists the —xtarget values for all platforms.
Table A-45 -xtarget Values for All Platforms
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Compiling for 64-bit Solaris software on SPARC or UltraSPARC V9 is indicated by the -m64 option. If you specify -xtarget with a flag other than native64 or generic64, you must also specify the -m64 option as follows: -xtarget=ultra... -m64. Otherwise, the compiler uses a 32-bit memory model.
Table A-46 -xtargetExpansions on SPARC Architecture
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Compiling for 64-bit Solaris software on 64-bit x86 platforms is indicated by the -m64 option. If you specify -xtarget with a flag other than native64 or generic64, you must also specify the -m64 option as follows: -xtarget=opteron ... -m64. Otherwise, the compiler uses a 32-bit memory model.
Table A-47 -xtarget Values on x86 Platforms
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On both SPARC and x86 devices, if –xtarget is not specified, –xtarget=generic is assumed.
The –xtarget option is a macro that permits a quick and easy specification of the -xarch, –xchip, and –xcache combinations that occur on commercially purchased platforms. The only meaning of –xtarget is in its expansion.
-xtarget=ultra means -xchip=ultra -xcache=16/32/1:512/64/1 -xarch=sparcvis.
Compilation for 64–bit SPARC V9 architecture indicated by the -m64 option. Setting –xtarget=ultra or ultra2 is not necessary or sufficient. If -xtarget is specified, any change to the —xarch, —xchip, or —xcache values must appear after the -xtarget. For example:
–xtarget=ultra3 -xarch=ultra
When you compile and link in separate steps, you must use the same -xtarget settings in the compile step and the link step.
Specify -xthreadvar to control the implementation of thread local variables. Use this option in conjunction with the __thread declaration specifier to take advantage of the compiler’s thread-local storage facility. After you declare the thread variables with the __thread specifier, specify -xthreadvar to enable the use of thread-local storage with position dependent code (non-PIC code) in dynamic (shared) libraries. For more information about how to use __thread, see 4.2 Thread-Local Storage.
The following table lists the possible values of o.
Table A-48 -xthreadvar Values
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If you do not specify -xthreadvar, the default used by the compiler depends upon whether position-independent code is enabled. If position-independent code is enabled, the option is set to -xthreadvar=dynamic. If position-independent code is disabled, the option is set to -xthreadvar=no%dynamic.
If you specify -xthreadvar but do not specify any arguments, the option is set to -xthreadvar=dynamic.
The -mt option must be used when compiling and linking files that use __thread.
If a dynamic library contains code that is not position-independent, you must specify -xthreadvar.
The linker cannot support the thread-variable equivalent of non-PIC code in dynamic libraries. Non-PIC thread variables are significantly faster, and hence should be the default for executables.
-xcode, -KPIC, -Kpic
Causes the CC driver to report execution time for the various compilation passes.
Enables or disables recognition of trigraph sequences as defined by the ISO/ANSI C standard.
If your source code has a literal string containing question marks (?) that the compiler is interpreting as a trigraph sequence, you can use the -xtrigraph=no suboption to turn off the recognition of trigraph sequences.
The following lists the possible values for -xtrigraphs.
Table A-49 -xtrigraphs Values
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When you do not include the -xtrigraphs option on the command line, the compiler assumes -xtrigraphs=yes.
If only -xtrigraphs is specified, the compiler assumes -xtrigraphs=yes.
Consider the following example source file named trigraphs_demo.cc.
#include <stdio.h>
int main ()
{
(void) printf("(\?\?) in a string appears as (??)\n");
return 0;
}
The following example shows the output when you compile this code with -xtrigraphs=yes.
example% CC -xtrigraphs=yes trigraphs_demo.cc example% a.out (??) in a string appears as (]
The following example shows the output when you compile this code with -xtrigraphs=no.
example% CC -xtrigraphs=no trigraphs_demo.cc example% a.out (??) in a string appears as (??)
For information about trigraphs, see the C User’s Guide chapter about transitioning to ANSI/ISO C.
This option directs the compiler to optimize loops by unrolling them where possible.
When n is 1, it is a suggestion to the compiler to not unroll loops.
When n is an integer greater than 1, -unroll=n causes the compiler to unroll loops n times.
Use this option if your code contains string or character literals that you want the compiler to convert to UTF-16 strings in the object file. Without this option, the compiler neither produces nor recognizes 16-bit character string literals. This option enables recognition of the U"ASCII-string" string literals as an array of unsigned short int. Because such strings are not yet part of any standard, this option enables recognition of non-standard C++.
Not all files have to be compiled with this option.
Specify -xustr=ascii_utf16_ushort if you need to support an internationalized application that uses ISO10646 UTF-16 string literals. You can turn off compiler recognition of U"ASCII_string" string or character literals by specifying -xustr=no. The right-most instance of this option on the command line overrides all previous instances.
You can specify -xustr=ascii_ustf16_ushort without also specifying a U"ASCII-string" string literal. To do so is not an error.
The default is -xustr=no. If you specify -xustr without an argument, the compiler won’t accept it and instead issues a warning. The default could change if the C or C++ standards define a meaning for the syntax.
The following example shows a string literal in quotes that is prepended by U. It also shows a command line that specifies -xustr
example% cat file.cc
const unsigned short *foo = U"foo";
const unsigned short bar[] = U"bar";
const unsigned short *fun() {return foo;}
example% CC -xustr=ascii_utf16_ushort file.cc -c
An 8-bit character literal can be prepended with U to form a 16-bit UTF-16 character of type unsigned short. For example:
const unsigned short x = U'x'; const unsigned short y = U'\x79';
Enables automatic generation of calls to the vector library functions or the generation of the SIMD (Single Instruction Multiple Data) instructions on x86 processors that support SIMD. You must use default rounding mode by specifying -fround=nearest when you use this option.
The -xvector option requires optimization level -xO3 or greater. Compilation will not proceed if the optimization level is unspecified or lower than -xO3, and a message is issued.
The possible values for a are listed in the following table. The no% prefix disables the associated suboption.
Table A-50 -xvector Suboptions
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The default is -xvector=simd on x86 and -xvector=%none on SPARC platforms. If you specify -xvector without a suboption, the compiler assumes -xvector=simd,lib on x86 Solaris, -xvector=lib on SPARC Solaris, and -xvector=simd on Linux platforms.
The compiler includes the libmvec libraries in the load step.
If you compile and link with separate commands, be sure to use -xvector in the linking CC command as well.
(SPARC only) Use the -xvis=[yes|no] command when you are using the assembly-language templates defined in the VIS Software Developers Kit (VSDK), or when using assembler inline code that uses VIS instructions and the vis.h header file.
The VIS instruction set is an extension to the SPARC v9 instruction set. Even though the UltraSPARC processors are 64-bit, there are many cases, especially in multimedia applications, when the data are limited to 8 or 16 bits in size. The VIS instructions can process four words of 16-bit data with one instruction so they greatly improve the performance of applications that handle new media such as imaging, linear algebra, signal processing, audio, video and networking.
The default is -xvis=no. Specifying -xvis is equivalent to specifying -xvis=yes.
Issues warnings about potential parallel-programming related problems that miht cause incorrect results when using OpenMP. Use with -xopenmp and OpenMP API directives.
The compiler issues warnings when it detects the following situations:
Loops are parallelized using MP directives with data dependencies between different loop iterations
OpenMP data-sharing attributes-clauses are problematic. For example, declaring a variable "shared" whose accesses in an OpenMP parallel region may cause a data race, or declaring a variable "private" whose value in a parallel region is used after the parallel region.
No warnings appear if all parallelization directives are processed without problems.
Note - Solaris Studio compilers support OpenMP API parallelization. Consequently, the MP pragmas directives are deprecated and are no longer supported. See the OpenMP API User’s Guide for information on migrating to the OpenMP API.
Converts all warnings to errors by returning nonzero exit status.
Specifies a new path for the location of component c.
If the location of a component is specified, then the new path name for the component is path/component-name. This option is passed to ld.
The following table lists the possible values for c.
Table A-51 -Y Flags
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You can have multiple -Y options on a command line. If more than one -Y option is applied to any one component, then the last occurrence holds.
Solaris Linker and Libraries Guide
Link editor option. For more information, see the ld(1) man page and the Oracle Solaris Linker and Libraries Guide.
See also A.2.98 -Xlinker arg
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