C.1.11 Preprocessing Directives (J.3.11)

• How sequences in both forms of header names are mapped to headers or external source file names (6.4.7).

  Source file characters are mapped to their corresponding ASCII values.

• Whether the value of a character constant in a constant expression that controls conditional inclusion matches the value of the same character constant in the execution character set (6.10.1).

  A character constant within a preprocessing directive has the same numeric value as it has within any other expression.

• Whether the value of a single-character character constant in a constant expression that controls conditional inclusion may have a negative value (6.10.1).

  Character constants in this context may have negative values (SPARC) (x86).

• The places that are searched for an included < > delimited header, and how the places are specified other header is identified (6.10.2).

  The location of header files depends upon the options specified on the command line, and in which file the #include directive appears. For more information, see 2.14 How to Specify Include Files.

• How the named source file is searched for in an included " " delimited header (6.10.2).

  The location of header files depends upon the options specified on the command line, and in which file the #include directive appears. For more information, see 2.14 How to Specify Include Files.

• The method by which preprocessing tokens (possibly resulting from macro expansion) in a #include directive are combined into a header name (6.10.2).

  All the tokens making up the header name (including white space) are treated as the file path used when searching for the header as described in 2.14 How to Specify Include Files.

• The nesting limit for #include processing (6.10.2).

  No limit is imposed by the compiler.

• Whether the # operator inserts a \ character before the \ character that begins a universal character name in a character constant or string literal (6.10.3.2).

  No.

• The behavior on each recognized non-STDC #pragma directive (6.10.6).

  See 2.8 Pragmas for a description of the behavior of each recognized non-STDC #pragma directive.

• The definitions for __DATE__ and __TIME__ when respectively, the date and time of translation are not available (6.10.8).

  These macros are always available from the environment.