mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-11-24 07:20:37 +00:00
b77d357ea3
* lib/dirent-private.h, m4/codeset.m4, m4/locale-fr.m4, m4/musl.m4: New files, from Gnulib.
242 lines
9.5 KiB
C
242 lines
9.5 KiB
C
/* ATTRIBUTE_* macros for using attributes in GCC and similar compilers
|
|
|
|
Copyright 2020-2023 Free Software Foundation, Inc.
|
|
|
|
This file is free software: you can redistribute it and/or modify
|
|
it under the terms of the GNU Lesser General Public License as
|
|
published by the Free Software Foundation; either version 2.1 of the
|
|
License, or (at your option) any later version.
|
|
|
|
This file is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public License
|
|
along with this program. If not, see <https://www.gnu.org/licenses/>. */
|
|
|
|
/* Written by Paul Eggert. */
|
|
|
|
/* Provide public ATTRIBUTE_* names for the private _GL_ATTRIBUTE_*
|
|
macros used within Gnulib. */
|
|
|
|
/* These attributes can be placed in two ways:
|
|
- At the start of a declaration (i.e. even before storage-class
|
|
specifiers!); then they apply to all entities that are declared
|
|
by the declaration.
|
|
- Immediately after the name of an entity being declared by the
|
|
declaration; then they apply to that entity only. */
|
|
|
|
#ifndef _GL_ATTRIBUTE_H
|
|
#define _GL_ATTRIBUTE_H
|
|
|
|
|
|
/* This file defines two types of attributes:
|
|
* C23 standard attributes. These have macro names that do not begin with
|
|
'ATTRIBUTE_'.
|
|
* Selected GCC attributes; see:
|
|
https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html
|
|
https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html
|
|
https://gcc.gnu.org/onlinedocs/gcc/Common-Type-Attributes.html
|
|
These names begin with 'ATTRIBUTE_' to avoid name clashes. */
|
|
|
|
|
|
/* This file uses _GL_ATTRIBUTE_ALLOC_SIZE, _GL_ATTRIBUTE_ALWAYS_INLINE,
|
|
_GL_ATTRIBUTE_ARTIFICIAL, _GL_ATTRIBUTE_COLD, _GL_ATTRIBUTE_CONST,
|
|
_GL_ATTRIBUTE_DEALLOC, _GL_ATTRIBUTE_DEPRECATED, _GL_ATTRIBUTE_ERROR,
|
|
_GL_ATTRIBUTE_WARNING, _GL_ATTRIBUTE_EXTERNALLY_VISIBLE,
|
|
_GL_ATTRIBUTE_FALLTHROUGH, _GL_ATTRIBUTE_FORMAT, _GL_ATTRIBUTE_LEAF,
|
|
_GL_ATTRIBUTE_MALLOC, _GL_ATTRIBUTE_MAY_ALIAS, _GL_ATTRIBUTE_MAYBE_UNUSED,
|
|
_GL_ATTRIBUTE_NODISCARD, _GL_ATTRIBUTE_NOINLINE, _GL_ATTRIBUTE_NONNULL,
|
|
_GL_ATTRIBUTE_NONSTRING, _GL_ATTRIBUTE_NOTHROW, _GL_ATTRIBUTE_PACKED,
|
|
_GL_ATTRIBUTE_PURE, _GL_ATTRIBUTE_RETURNS_NONNULL,
|
|
_GL_ATTRIBUTE_SENTINEL. */
|
|
#if !_GL_CONFIG_H_INCLUDED
|
|
#error "Please include config.h first."
|
|
#endif
|
|
|
|
|
|
/* =============== Attributes for specific kinds of functions =============== */
|
|
|
|
/* Attributes for functions that should not be used. */
|
|
|
|
/* Warn if the entity is used. */
|
|
/* Applies to:
|
|
- function, variable,
|
|
- struct, union, struct/union member,
|
|
- enumeration, enumeration item,
|
|
- typedef,
|
|
in C++ also: namespace, class, template specialization. */
|
|
#define DEPRECATED _GL_ATTRIBUTE_DEPRECATED
|
|
|
|
/* If a function call is not optimized way, warn with MSG. */
|
|
/* Applies to: functions. */
|
|
#define ATTRIBUTE_WARNING(msg) _GL_ATTRIBUTE_WARNING (msg)
|
|
|
|
/* If a function call is not optimized way, report an error with MSG. */
|
|
/* Applies to: functions. */
|
|
#define ATTRIBUTE_ERROR(msg) _GL_ATTRIBUTE_ERROR (msg)
|
|
|
|
|
|
/* Attributes for memory-allocating functions. */
|
|
|
|
/* The function returns a pointer to freshly allocated memory. */
|
|
/* Applies to: functions. */
|
|
#define ATTRIBUTE_MALLOC _GL_ATTRIBUTE_MALLOC
|
|
|
|
/* ATTRIBUTE_ALLOC_SIZE ((N)) - The Nth argument of the function
|
|
is the size of the returned memory block.
|
|
ATTRIBUTE_ALLOC_SIZE ((M, N)) - Multiply the Mth and Nth arguments
|
|
to determine the size of the returned memory block. */
|
|
/* Applies to: function, pointer to function, function types. */
|
|
#define ATTRIBUTE_ALLOC_SIZE(args) _GL_ATTRIBUTE_ALLOC_SIZE (args)
|
|
|
|
/* ATTRIBUTE_DEALLOC (F, I) declares that the function returns pointers
|
|
that can be freed by passing them as the Ith argument to the
|
|
function F.
|
|
ATTRIBUTE_DEALLOC_FREE declares that the function returns pointers that
|
|
can be freed via 'free'; it can be used only after declaring 'free'. */
|
|
/* Applies to: functions. Cannot be used on inline functions. */
|
|
#define ATTRIBUTE_DEALLOC(f, i) _GL_ATTRIBUTE_DEALLOC(f, i)
|
|
#define ATTRIBUTE_DEALLOC_FREE _GL_ATTRIBUTE_DEALLOC_FREE
|
|
|
|
/* Attributes for variadic functions. */
|
|
|
|
/* The variadic function expects a trailing NULL argument.
|
|
ATTRIBUTE_SENTINEL () - The last argument is NULL (requires C99).
|
|
ATTRIBUTE_SENTINEL ((N)) - The (N+1)st argument from the end is NULL. */
|
|
/* Applies to: functions. */
|
|
#define ATTRIBUTE_SENTINEL(pos) _GL_ATTRIBUTE_SENTINEL (pos)
|
|
|
|
|
|
/* ================== Attributes for compiler diagnostics ================== */
|
|
|
|
/* Attributes that help the compiler diagnose programmer mistakes.
|
|
Some of them may also help for some compiler optimizations. */
|
|
|
|
/* ATTRIBUTE_FORMAT ((ARCHETYPE, STRING-INDEX, FIRST-TO-CHECK)) -
|
|
The STRING-INDEXth function argument is a format string of style
|
|
ARCHETYPE, which is one of:
|
|
printf, gnu_printf
|
|
scanf, gnu_scanf,
|
|
strftime, gnu_strftime,
|
|
strfmon,
|
|
or the same thing prefixed and suffixed with '__'.
|
|
If FIRST-TO-CHECK is not 0, arguments starting at FIRST-TO_CHECK
|
|
are suitable for the format string. */
|
|
/* Applies to: functions. */
|
|
#define ATTRIBUTE_FORMAT(spec) _GL_ATTRIBUTE_FORMAT (spec)
|
|
|
|
/* ATTRIBUTE_NONNULL ((N1, N2,...)) - Arguments N1, N2,... must not be NULL.
|
|
ATTRIBUTE_NONNULL () - All pointer arguments must not be null. */
|
|
/* Applies to: functions. */
|
|
#define ATTRIBUTE_NONNULL(args) _GL_ATTRIBUTE_NONNULL (args)
|
|
|
|
/* The function's return value is a non-NULL pointer. */
|
|
/* Applies to: functions. */
|
|
#define ATTRIBUTE_RETURNS_NONNULL _GL_ATTRIBUTE_RETURNS_NONNULL
|
|
|
|
/* Warn if the caller does not use the return value,
|
|
unless the caller uses something like ignore_value. */
|
|
/* Applies to: function, enumeration, class. */
|
|
#define NODISCARD _GL_ATTRIBUTE_NODISCARD
|
|
|
|
|
|
/* Attributes that disable false alarms when the compiler diagnoses
|
|
programmer "mistakes". */
|
|
|
|
/* Do not warn if the entity is not used. */
|
|
/* Applies to:
|
|
- function, variable,
|
|
- struct, union, struct/union member,
|
|
- enumeration, enumeration item,
|
|
- typedef,
|
|
in C++ also: class. */
|
|
#define MAYBE_UNUSED _GL_ATTRIBUTE_MAYBE_UNUSED
|
|
|
|
/* The contents of a character array is not meant to be NUL-terminated. */
|
|
/* Applies to: struct/union members and variables that are arrays of element
|
|
type '[[un]signed] char'. */
|
|
#define ATTRIBUTE_NONSTRING _GL_ATTRIBUTE_NONSTRING
|
|
|
|
/* Do not warn if control flow falls through to the immediately
|
|
following 'case' or 'default' label. */
|
|
/* Applies to: Empty statement (;), inside a 'switch' statement. */
|
|
#define FALLTHROUGH _GL_ATTRIBUTE_FALLTHROUGH
|
|
|
|
|
|
/* ================== Attributes for debugging information ================== */
|
|
|
|
/* Attributes regarding debugging information emitted by the compiler. */
|
|
|
|
/* Omit the function from stack traces when debugging. */
|
|
/* Applies to: function. */
|
|
#define ATTRIBUTE_ARTIFICIAL _GL_ATTRIBUTE_ARTIFICIAL
|
|
|
|
/* Make the entity visible to debuggers etc., even with '-fwhole-program'. */
|
|
/* Applies to: functions, variables. */
|
|
#define ATTRIBUTE_EXTERNALLY_VISIBLE _GL_ATTRIBUTE_EXTERNALLY_VISIBLE
|
|
|
|
|
|
/* ========== Attributes that mainly direct compiler optimizations ========== */
|
|
|
|
/* The function does not throw exceptions. */
|
|
/* Applies to: functions. */
|
|
#define ATTRIBUTE_NOTHROW _GL_ATTRIBUTE_NOTHROW
|
|
|
|
/* Do not inline the function. */
|
|
/* Applies to: functions. */
|
|
#define ATTRIBUTE_NOINLINE _GL_ATTRIBUTE_NOINLINE
|
|
|
|
/* Always inline the function, and report an error if the compiler
|
|
cannot inline. */
|
|
/* Applies to: function. */
|
|
#define ATTRIBUTE_ALWAYS_INLINE _GL_ATTRIBUTE_ALWAYS_INLINE
|
|
|
|
/* It is OK for a compiler to omit duplicate calls with the same arguments.
|
|
This attribute is safe for a function that neither depends on
|
|
nor affects observable state, and always returns exactly once -
|
|
e.g., does not loop forever, and does not call longjmp.
|
|
(This attribute is stricter than ATTRIBUTE_PURE.) */
|
|
/* Applies to: functions. */
|
|
#define ATTRIBUTE_CONST _GL_ATTRIBUTE_CONST
|
|
|
|
/* It is OK for a compiler to omit duplicate calls with the same
|
|
arguments if observable state is not changed between calls.
|
|
This attribute is safe for a function that does not affect
|
|
observable state, and always returns exactly once.
|
|
(This attribute is looser than ATTRIBUTE_CONST.) */
|
|
/* Applies to: functions. */
|
|
#define ATTRIBUTE_PURE _GL_ATTRIBUTE_PURE
|
|
|
|
/* The function is rarely executed. */
|
|
/* Applies to: functions. */
|
|
#define ATTRIBUTE_COLD _GL_ATTRIBUTE_COLD
|
|
|
|
/* If called from some other compilation unit, the function executes
|
|
code from that unit only by return or by exception handling,
|
|
letting the compiler optimize that unit more aggressively. */
|
|
/* Applies to: functions. */
|
|
#define ATTRIBUTE_LEAF _GL_ATTRIBUTE_LEAF
|
|
|
|
/* For struct members: The member has the smallest possible alignment.
|
|
For struct, union, class: All members have the smallest possible alignment,
|
|
minimizing the memory required. */
|
|
/* Applies to: struct members, struct, union,
|
|
in C++ also: class. */
|
|
#define ATTRIBUTE_PACKED _GL_ATTRIBUTE_PACKED
|
|
|
|
|
|
/* ================ Attributes that make invalid code valid ================ */
|
|
|
|
/* Attributes that prevent fatal compiler optimizations for code that is not
|
|
fully ISO C compliant. */
|
|
|
|
/* Pointers to the type may point to the same storage as pointers to
|
|
other types, thus disabling strict aliasing optimization. */
|
|
/* Applies to: types. */
|
|
#define ATTRIBUTE_MAY_ALIAS _GL_ATTRIBUTE_MAY_ALIAS
|
|
|
|
|
|
#endif /* _GL_ATTRIBUTE_H */
|