From d592f1c398da37535d3c528d1a511a32d8b9b3ba Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Thu, 22 Jul 2004 21:12:20 +0100 Subject: [PATCH] implement-c.texi: New file. * doc/implement-c.texi: New file. * doc/extend.texi (C Implementation): Move to there. * doc/gcc.texi: Include implement-c.texi. * Makefile.in (TEXI_GCC_FILES): Add implement-c.texi. From-SVN: r85058 --- gcc/ChangeLog | 7 + gcc/Makefile.in | 3 +- gcc/doc/extend.texi | 400 -------------------------------------- gcc/doc/gcc.texi | 1 + gcc/doc/implement-c.texi | 403 +++++++++++++++++++++++++++++++++++++++ 5 files changed, 413 insertions(+), 401 deletions(-) create mode 100644 gcc/doc/implement-c.texi diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 12aac93f7ba..5041b3f09f4 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2004-07-22 Joseph S. Myers + + * doc/implement-c.texi: New file. + * doc/extend.texi (C Implementation): Move to there. + * doc/gcc.texi: Include implement-c.texi. + * Makefile.in (TEXI_GCC_FILES): Add implement-c.texi. + 2004-07-22 Jason Merrill * integrate.c (copy_decl_for_inlining): Remove invisible reference diff --git a/gcc/Makefile.in b/gcc/Makefile.in index 32bb1fe513e..e57458b1302 100644 --- a/gcc/Makefile.in +++ b/gcc/Makefile.in @@ -2911,7 +2911,8 @@ TEXI_CPP_FILES = cpp.texi fdl.texi cppenv.texi cppopts.texi TEXI_GCC_FILES = gcc.texi gcc-common.texi frontends.texi standards.texi \ invoke.texi extend.texi md.texi objc.texi gcov.texi trouble.texi \ bugreport.texi service.texi contribute.texi compat.texi funding.texi \ - gnu.texi gpl.texi fdl.texi contrib.texi cppenv.texi cppopts.texi + gnu.texi gpl.texi fdl.texi contrib.texi cppenv.texi cppopts.texi \ + implement-c.texi TEXI_GCCINT_FILES = gccint.texi gcc-common.texi contribute.texi makefile.texi \ configterms.texi portability.texi interface.texi passes.texi \ diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi index 3374bab49a5..60498171bc4 100644 --- a/gcc/doc/extend.texi +++ b/gcc/doc/extend.texi @@ -3,406 +3,6 @@ @c This is part of the GCC manual. @c For copying conditions, see the file gcc.texi. -@node C Implementation -@chapter C Implementation-defined behavior -@cindex implementation-defined behavior, C language - -A conforming implementation of ISO C is required to document its -choice of behavior in each of the areas that are designated -``implementation defined.'' The following lists all such areas, -along with the section number from the ISO/IEC 9899:1999 standard. - -@menu -* Translation implementation:: -* Environment implementation:: -* Identifiers implementation:: -* Characters implementation:: -* Integers implementation:: -* Floating point implementation:: -* Arrays and pointers implementation:: -* Hints implementation:: -* Structures unions enumerations and bit-fields implementation:: -* Qualifiers implementation:: -* Preprocessing directives implementation:: -* Library functions implementation:: -* Architecture implementation:: -* Locale-specific behavior implementation:: -@end menu - -@node Translation implementation -@section Translation - -@itemize @bullet -@item -@cite{How a diagnostic is identified (3.10, 5.1.1.3).} - -Diagnostics consist of all the output sent to stderr by GCC. - -@item -@cite{Whether each nonempty sequence of white-space characters other than -new-line is retained or replaced by one space character in translation -phase 3 (5.1.1.2).} -@end itemize - -@node Environment implementation -@section Environment - -The behavior of these points are dependent on the implementation -of the C library, and are not defined by GCC itself. - -@node Identifiers implementation -@section Identifiers - -@itemize @bullet -@item -@cite{Which additional multibyte characters may appear in identifiers -and their correspondence to universal character names (6.4.2).} - -@item -@cite{The number of significant initial characters in an identifier -(5.2.4.1, 6.4.2).} - -For internal names, all characters are significant. For external names, -the number of significant characters are defined by the linker; for -almost all targets, all characters are significant. - -@end itemize - -@node Characters implementation -@section Characters - -@itemize @bullet -@item -@cite{The number of bits in a byte (3.6).} - -@item -@cite{The values of the members of the execution character set (5.2.1).} - -@item -@cite{The unique value of the member of the execution character set produced -for each of the standard alphabetic escape sequences (5.2.2).} - -@item -@cite{The value of a @code{char} object into which has been stored any -character other than a member of the basic execution character set (6.2.5).} - -@item -@cite{Which of @code{signed char} or @code{unsigned char} has the same range, -representation, and behavior as ``plain'' @code{char} (6.2.5, 6.3.1.1).} - -@item -@cite{The mapping of members of the source character set (in character -constants and string literals) to members of the execution character -set (6.4.4.4, 5.1.1.2).} - -@item -@cite{The value of an integer character constant containing more than one -character or containing a character or escape sequence that does not map -to a single-byte execution character (6.4.4.4).} - -@item -@cite{The value of a wide character constant containing more than one -multibyte character, or containing a multibyte character or escape -sequence not represented in the extended execution character set (6.4.4.4).} - -@item -@cite{The current locale used to convert a wide character constant consisting -of a single multibyte character that maps to a member of the extended -execution character set into a corresponding wide character code (6.4.4.4).} - -@item -@cite{The current locale used to convert a wide string literal into -corresponding wide character codes (6.4.5).} - -@item -@cite{The value of a string literal containing a multibyte character or escape -sequence not represented in the execution character set (6.4.5).} -@end itemize - -@node Integers implementation -@section Integers - -@itemize @bullet -@item -@cite{Any extended integer types that exist in the implementation (6.2.5).} - -@item -@cite{Whether signed integer types are represented using sign and magnitude, -two's complement, or one's complement, and whether the extraordinary value -is a trap representation or an ordinary value (6.2.6.2).} - -GCC supports only two's complement integer types, and all bit patterns -are ordinary values. - -@item -@cite{The rank of any extended integer type relative to another extended -integer type with the same precision (6.3.1.1).} - -@item -@cite{The result of, or the signal raised by, converting an integer to a -signed integer type when the value cannot be represented in an object of -that type (6.3.1.3).} - -@item -@cite{The results of some bitwise operations on signed integers (6.5).} -@end itemize - -@node Floating point implementation -@section Floating point - -@itemize @bullet -@item -@cite{The accuracy of the floating-point operations and of the library -functions in @code{} and @code{} that return floating-point -results (5.2.4.2.2).} - -@item -@cite{The rounding behaviors characterized by non-standard values -of @code{FLT_ROUNDS} @gol -(5.2.4.2.2).} - -@item -@cite{The evaluation methods characterized by non-standard negative -values of @code{FLT_EVAL_METHOD} (5.2.4.2.2).} - -@item -@cite{The direction of rounding when an integer is converted to a -floating-point number that cannot exactly represent the original -value (6.3.1.4).} - -@item -@cite{The direction of rounding when a floating-point number is -converted to a narrower floating-point number (6.3.1.5).} - -@item -@cite{How the nearest representable value or the larger or smaller -representable value immediately adjacent to the nearest representable -value is chosen for certain floating constants (6.4.4.2).} - -@item -@cite{Whether and how floating expressions are contracted when not -disallowed by the @code{FP_CONTRACT} pragma (6.5).} - -@item -@cite{The default state for the @code{FENV_ACCESS} pragma (7.6.1).} - -@item -@cite{Additional floating-point exceptions, rounding modes, environments, -and classifications, and their macro names (7.6, 7.12).} - -@item -@cite{The default state for the @code{FP_CONTRACT} pragma (7.12.2).} - -@item -@cite{Whether the ``inexact'' floating-point exception can be raised -when the rounded result actually does equal the mathematical result -in an IEC 60559 conformant implementation (F.9).} - -@item -@cite{Whether the ``underflow'' (and ``inexact'') floating-point -exception can be raised when a result is tiny but not inexact in an -IEC 60559 conformant implementation (F.9).} - -@end itemize - -@node Arrays and pointers implementation -@section Arrays and pointers - -@itemize @bullet -@item -@cite{The result of converting a pointer to an integer or -vice versa (6.3.2.3).} - -A cast from pointer to integer discards most-significant bits if the -pointer representation is larger than the integer type, -sign-extends@footnote{Future versions of GCC may zero-extend, or use -a target-defined @code{ptr_extend} pattern. Do not rely on sign extension.} -if the pointer representation is smaller than the integer type, otherwise -the bits are unchanged. -@c ??? We've always claimed that pointers were unsigned entities. -@c Shouldn't we therefore be doing zero-extension? If so, the bug -@c is in convert_to_integer, where we call type_for_size and request -@c a signed integral type. On the other hand, it might be most useful -@c for the target if we extend according to POINTERS_EXTEND_UNSIGNED. - -A cast from integer to pointer discards most-significant bits if the -pointer representation is smaller than the integer type, extends according -to the signedness of the integer type if the pointer representation -is larger than the integer type, otherwise the bits are unchanged. - -When casting from pointer to integer and back again, the resulting -pointer must reference the same object as the original pointer, otherwise -the behavior is undefined. That is, one may not use integer arithmetic to -avoid the undefined behavior of pointer arithmetic as proscribed in 6.5.6/8. - -@item -@cite{The size of the result of subtracting two pointers to elements -of the same array (6.5.6).} - -@end itemize - -@node Hints implementation -@section Hints - -@itemize @bullet -@item -@cite{The extent to which suggestions made by using the @code{register} -storage-class specifier are effective (6.7.1).} - -The @code{register} specifier affects code generation only in these ways: - -@itemize @bullet -@item -When used as part of the register variable extension, see -@ref{Explicit Reg Vars}. - -@item -When @option{-O0} is in use, the compiler allocates distinct stack -memory for all variables that do not have the @code{register} -storage-class specifier; if @code{register} is specified, the variable -may have a shorter lifespan than the code would indicate and may never -be placed in memory. - -@item -On some rare x86 targets, @code{setjmp} doesn't save the registers in -all circumstances. In those cases, GCC doesn't allocate any variables -in registers unless they are marked @code{register}. - -@end itemize - -@item -@cite{The extent to which suggestions made by using the inline function -specifier are effective (6.7.4).} - -GCC will not inline any functions if the @option{-fno-inline} option is -used or if @option{-O0} is used. Otherwise, GCC may still be unable to -inline a function for many reasons; the @option{-Winline} option may be -used to determine if a function has not been inlined and why not. - -@end itemize - -@node Structures unions enumerations and bit-fields implementation -@section Structures, unions, enumerations, and bit-fields - -@itemize @bullet -@item -@cite{Whether a ``plain'' int bit-field is treated as a @code{signed int} -bit-field or as an @code{unsigned int} bit-field (6.7.2, 6.7.2.1).} - -@item -@cite{Allowable bit-field types other than @code{_Bool}, @code{signed int}, -and @code{unsigned int} (6.7.2.1).} - -@item -@cite{Whether a bit-field can straddle a storage-unit boundary (6.7.2.1).} - -@item -@cite{The order of allocation of bit-fields within a unit (6.7.2.1).} - -@item -@cite{The alignment of non-bit-field members of structures (6.7.2.1).} - -@item -@cite{The integer type compatible with each enumerated type (6.7.2.2).} - -@end itemize - -@node Qualifiers implementation -@section Qualifiers - -@itemize @bullet -@item -@cite{What constitutes an access to an object that has volatile-qualified -type (6.7.3).} - -@end itemize - -@node Preprocessing directives implementation -@section Preprocessing directives - -@itemize @bullet -@item -@cite{How sequences in both forms of header names are mapped to headers -or external source file names (6.4.7).} - -@item -@cite{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).} - -@item -@cite{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).} - -@item -@cite{The places that are searched for an included @samp{<>} delimited -header, and how the places are specified or the header is -identified (6.10.2).} - -@item -@cite{How the named source file is searched for in an included @samp{""} -delimited header (6.10.2).} - -@item -@cite{The method by which preprocessing tokens (possibly resulting from -macro expansion) in a @code{#include} directive are combined into a header -name (6.10.2).} - -@item -@cite{The nesting limit for @code{#include} processing (6.10.2).} - -GCC imposes a limit of 200 nested @code{#include}s. - -@item -@cite{Whether the @samp{#} operator inserts a @samp{\} character before -the @samp{\} character that begins a universal character name in a -character constant or string literal (6.10.3.2).} - -@item -@cite{The behavior on each recognized non-@code{STDC #pragma} -directive (6.10.6).} - -@item -@cite{The definitions for @code{__DATE__} and @code{__TIME__} when -respectively, the date and time of translation are not available (6.10.8).} - -If the date and time are not available, @code{__DATE__} expands to -@code{@w{"??? ?? ????"}} and @code{__TIME__} expands to -@code{"??:??:??"}. - -@end itemize - -@node Library functions implementation -@section Library functions - -The behavior of these points are dependent on the implementation -of the C library, and are not defined by GCC itself. - -@node Architecture implementation -@section Architecture - -@itemize @bullet -@item -@cite{The values or expressions assigned to the macros specified in the -headers @code{}, @code{}, and @code{} -(5.2.4.2, 7.18.2, 7.18.3).} - -@item -@cite{The number, order, and encoding of bytes in any object -(when not explicitly specified in this International Standard) (6.2.6.1).} - -@item -@cite{The value of the result of the sizeof operator (6.5.3.4).} - -@end itemize - -@node Locale-specific behavior implementation -@section Locale-specific behavior - -The behavior of these points are dependent on the implementation -of the C library, and are not defined by GCC itself. - @node C Extensions @chapter Extensions to the C Language Family @cindex extensions, C language diff --git a/gcc/doc/gcc.texi b/gcc/doc/gcc.texi index 07dfd08e4d3..6eac7efd6aa 100644 --- a/gcc/doc/gcc.texi +++ b/gcc/doc/gcc.texi @@ -160,6 +160,7 @@ Introduction, gccint, GNU Compiler Collection (GCC) Internals}. @include frontends.texi @include standards.texi @include invoke.texi +@include implement-c.texi @include extend.texi @include objc.texi @include compat.texi diff --git a/gcc/doc/implement-c.texi b/gcc/doc/implement-c.texi new file mode 100644 index 00000000000..f179877df66 --- /dev/null +++ b/gcc/doc/implement-c.texi @@ -0,0 +1,403 @@ +@c Copyright (C) 2001,2002,2003,2004 Free Software Foundation, Inc. +@c This is part of the GCC manual. +@c For copying conditions, see the file gcc.texi. + +@node C Implementation +@chapter C Implementation-defined behavior +@cindex implementation-defined behavior, C language + +A conforming implementation of ISO C is required to document its +choice of behavior in each of the areas that are designated +``implementation defined.'' The following lists all such areas, +along with the section number from the ISO/IEC 9899:1999 standard. + +@menu +* Translation implementation:: +* Environment implementation:: +* Identifiers implementation:: +* Characters implementation:: +* Integers implementation:: +* Floating point implementation:: +* Arrays and pointers implementation:: +* Hints implementation:: +* Structures unions enumerations and bit-fields implementation:: +* Qualifiers implementation:: +* Preprocessing directives implementation:: +* Library functions implementation:: +* Architecture implementation:: +* Locale-specific behavior implementation:: +@end menu + +@node Translation implementation +@section Translation + +@itemize @bullet +@item +@cite{How a diagnostic is identified (3.10, 5.1.1.3).} + +Diagnostics consist of all the output sent to stderr by GCC. + +@item +@cite{Whether each nonempty sequence of white-space characters other than +new-line is retained or replaced by one space character in translation +phase 3 (5.1.1.2).} +@end itemize + +@node Environment implementation +@section Environment + +The behavior of these points are dependent on the implementation +of the C library, and are not defined by GCC itself. + +@node Identifiers implementation +@section Identifiers + +@itemize @bullet +@item +@cite{Which additional multibyte characters may appear in identifiers +and their correspondence to universal character names (6.4.2).} + +@item +@cite{The number of significant initial characters in an identifier +(5.2.4.1, 6.4.2).} + +For internal names, all characters are significant. For external names, +the number of significant characters are defined by the linker; for +almost all targets, all characters are significant. + +@end itemize + +@node Characters implementation +@section Characters + +@itemize @bullet +@item +@cite{The number of bits in a byte (3.6).} + +@item +@cite{The values of the members of the execution character set (5.2.1).} + +@item +@cite{The unique value of the member of the execution character set produced +for each of the standard alphabetic escape sequences (5.2.2).} + +@item +@cite{The value of a @code{char} object into which has been stored any +character other than a member of the basic execution character set (6.2.5).} + +@item +@cite{Which of @code{signed char} or @code{unsigned char} has the same range, +representation, and behavior as ``plain'' @code{char} (6.2.5, 6.3.1.1).} + +@item +@cite{The mapping of members of the source character set (in character +constants and string literals) to members of the execution character +set (6.4.4.4, 5.1.1.2).} + +@item +@cite{The value of an integer character constant containing more than one +character or containing a character or escape sequence that does not map +to a single-byte execution character (6.4.4.4).} + +@item +@cite{The value of a wide character constant containing more than one +multibyte character, or containing a multibyte character or escape +sequence not represented in the extended execution character set (6.4.4.4).} + +@item +@cite{The current locale used to convert a wide character constant consisting +of a single multibyte character that maps to a member of the extended +execution character set into a corresponding wide character code (6.4.4.4).} + +@item +@cite{The current locale used to convert a wide string literal into +corresponding wide character codes (6.4.5).} + +@item +@cite{The value of a string literal containing a multibyte character or escape +sequence not represented in the execution character set (6.4.5).} +@end itemize + +@node Integers implementation +@section Integers + +@itemize @bullet +@item +@cite{Any extended integer types that exist in the implementation (6.2.5).} + +@item +@cite{Whether signed integer types are represented using sign and magnitude, +two's complement, or one's complement, and whether the extraordinary value +is a trap representation or an ordinary value (6.2.6.2).} + +GCC supports only two's complement integer types, and all bit patterns +are ordinary values. + +@item +@cite{The rank of any extended integer type relative to another extended +integer type with the same precision (6.3.1.1).} + +@item +@cite{The result of, or the signal raised by, converting an integer to a +signed integer type when the value cannot be represented in an object of +that type (6.3.1.3).} + +@item +@cite{The results of some bitwise operations on signed integers (6.5).} +@end itemize + +@node Floating point implementation +@section Floating point + +@itemize @bullet +@item +@cite{The accuracy of the floating-point operations and of the library +functions in @code{} and @code{} that return floating-point +results (5.2.4.2.2).} + +@item +@cite{The rounding behaviors characterized by non-standard values +of @code{FLT_ROUNDS} @gol +(5.2.4.2.2).} + +@item +@cite{The evaluation methods characterized by non-standard negative +values of @code{FLT_EVAL_METHOD} (5.2.4.2.2).} + +@item +@cite{The direction of rounding when an integer is converted to a +floating-point number that cannot exactly represent the original +value (6.3.1.4).} + +@item +@cite{The direction of rounding when a floating-point number is +converted to a narrower floating-point number (6.3.1.5).} + +@item +@cite{How the nearest representable value or the larger or smaller +representable value immediately adjacent to the nearest representable +value is chosen for certain floating constants (6.4.4.2).} + +@item +@cite{Whether and how floating expressions are contracted when not +disallowed by the @code{FP_CONTRACT} pragma (6.5).} + +@item +@cite{The default state for the @code{FENV_ACCESS} pragma (7.6.1).} + +@item +@cite{Additional floating-point exceptions, rounding modes, environments, +and classifications, and their macro names (7.6, 7.12).} + +@item +@cite{The default state for the @code{FP_CONTRACT} pragma (7.12.2).} + +@item +@cite{Whether the ``inexact'' floating-point exception can be raised +when the rounded result actually does equal the mathematical result +in an IEC 60559 conformant implementation (F.9).} + +@item +@cite{Whether the ``underflow'' (and ``inexact'') floating-point +exception can be raised when a result is tiny but not inexact in an +IEC 60559 conformant implementation (F.9).} + +@end itemize + +@node Arrays and pointers implementation +@section Arrays and pointers + +@itemize @bullet +@item +@cite{The result of converting a pointer to an integer or +vice versa (6.3.2.3).} + +A cast from pointer to integer discards most-significant bits if the +pointer representation is larger than the integer type, +sign-extends@footnote{Future versions of GCC may zero-extend, or use +a target-defined @code{ptr_extend} pattern. Do not rely on sign extension.} +if the pointer representation is smaller than the integer type, otherwise +the bits are unchanged. +@c ??? We've always claimed that pointers were unsigned entities. +@c Shouldn't we therefore be doing zero-extension? If so, the bug +@c is in convert_to_integer, where we call type_for_size and request +@c a signed integral type. On the other hand, it might be most useful +@c for the target if we extend according to POINTERS_EXTEND_UNSIGNED. + +A cast from integer to pointer discards most-significant bits if the +pointer representation is smaller than the integer type, extends according +to the signedness of the integer type if the pointer representation +is larger than the integer type, otherwise the bits are unchanged. + +When casting from pointer to integer and back again, the resulting +pointer must reference the same object as the original pointer, otherwise +the behavior is undefined. That is, one may not use integer arithmetic to +avoid the undefined behavior of pointer arithmetic as proscribed in 6.5.6/8. + +@item +@cite{The size of the result of subtracting two pointers to elements +of the same array (6.5.6).} + +@end itemize + +@node Hints implementation +@section Hints + +@itemize @bullet +@item +@cite{The extent to which suggestions made by using the @code{register} +storage-class specifier are effective (6.7.1).} + +The @code{register} specifier affects code generation only in these ways: + +@itemize @bullet +@item +When used as part of the register variable extension, see +@ref{Explicit Reg Vars}. + +@item +When @option{-O0} is in use, the compiler allocates distinct stack +memory for all variables that do not have the @code{register} +storage-class specifier; if @code{register} is specified, the variable +may have a shorter lifespan than the code would indicate and may never +be placed in memory. + +@item +On some rare x86 targets, @code{setjmp} doesn't save the registers in +all circumstances. In those cases, GCC doesn't allocate any variables +in registers unless they are marked @code{register}. + +@end itemize + +@item +@cite{The extent to which suggestions made by using the inline function +specifier are effective (6.7.4).} + +GCC will not inline any functions if the @option{-fno-inline} option is +used or if @option{-O0} is used. Otherwise, GCC may still be unable to +inline a function for many reasons; the @option{-Winline} option may be +used to determine if a function has not been inlined and why not. + +@end itemize + +@node Structures unions enumerations and bit-fields implementation +@section Structures, unions, enumerations, and bit-fields + +@itemize @bullet +@item +@cite{Whether a ``plain'' int bit-field is treated as a @code{signed int} +bit-field or as an @code{unsigned int} bit-field (6.7.2, 6.7.2.1).} + +@item +@cite{Allowable bit-field types other than @code{_Bool}, @code{signed int}, +and @code{unsigned int} (6.7.2.1).} + +@item +@cite{Whether a bit-field can straddle a storage-unit boundary (6.7.2.1).} + +@item +@cite{The order of allocation of bit-fields within a unit (6.7.2.1).} + +@item +@cite{The alignment of non-bit-field members of structures (6.7.2.1).} + +@item +@cite{The integer type compatible with each enumerated type (6.7.2.2).} + +@end itemize + +@node Qualifiers implementation +@section Qualifiers + +@itemize @bullet +@item +@cite{What constitutes an access to an object that has volatile-qualified +type (6.7.3).} + +@end itemize + +@node Preprocessing directives implementation +@section Preprocessing directives + +@itemize @bullet +@item +@cite{How sequences in both forms of header names are mapped to headers +or external source file names (6.4.7).} + +@item +@cite{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).} + +@item +@cite{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).} + +@item +@cite{The places that are searched for an included @samp{<>} delimited +header, and how the places are specified or the header is +identified (6.10.2).} + +@item +@cite{How the named source file is searched for in an included @samp{""} +delimited header (6.10.2).} + +@item +@cite{The method by which preprocessing tokens (possibly resulting from +macro expansion) in a @code{#include} directive are combined into a header +name (6.10.2).} + +@item +@cite{The nesting limit for @code{#include} processing (6.10.2).} + +GCC imposes a limit of 200 nested @code{#include}s. + +@item +@cite{Whether the @samp{#} operator inserts a @samp{\} character before +the @samp{\} character that begins a universal character name in a +character constant or string literal (6.10.3.2).} + +@item +@cite{The behavior on each recognized non-@code{STDC #pragma} +directive (6.10.6).} + +@item +@cite{The definitions for @code{__DATE__} and @code{__TIME__} when +respectively, the date and time of translation are not available (6.10.8).} + +If the date and time are not available, @code{__DATE__} expands to +@code{@w{"??? ?? ????"}} and @code{__TIME__} expands to +@code{"??:??:??"}. + +@end itemize + +@node Library functions implementation +@section Library functions + +The behavior of these points are dependent on the implementation +of the C library, and are not defined by GCC itself. + +@node Architecture implementation +@section Architecture + +@itemize @bullet +@item +@cite{The values or expressions assigned to the macros specified in the +headers @code{}, @code{}, and @code{} +(5.2.4.2, 7.18.2, 7.18.3).} + +@item +@cite{The number, order, and encoding of bytes in any object +(when not explicitly specified in this International Standard) (6.2.6.1).} + +@item +@cite{The value of the result of the sizeof operator (6.5.3.4).} + +@end itemize + +@node Locale-specific behavior implementation +@section Locale-specific behavior + +The behavior of these points are dependent on the implementation +of the C library, and are not defined by GCC itself. -- 2.30.2