-# gnulib-common.m4 serial 75
+# gnulib-common.m4 serial 75a
dnl Copyright (C) 2007-2023 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
by the Nth argument of the function is the size of the returned memory block.
*/
/* Applies to: function, pointer to function, function types. */
-#if _GL_HAS_ATTRIBUTE (alloc_size)
-# define _GL_ATTRIBUTE_ALLOC_SIZE(args) __attribute__ ((__alloc_size__ args))
-#else
-# define _GL_ATTRIBUTE_ALLOC_SIZE(args)
+#ifndef _GL_ATTRIBUTE_ALLOC_SIZE
+# if _GL_HAS_ATTRIBUTE (alloc_size)
+# define _GL_ATTRIBUTE_ALLOC_SIZE(args) __attribute__ ((__alloc_size__ args))
+# else
+# define _GL_ATTRIBUTE_ALLOC_SIZE(args)
+# endif
#endif
/* _GL_ATTRIBUTE_ALWAYS_INLINE tells that the compiler should always inline the
function and report an error if it cannot do so. */
/* Applies to: function. */
-#if _GL_HAS_ATTRIBUTE (always_inline)
-# define _GL_ATTRIBUTE_ALWAYS_INLINE __attribute__ ((__always_inline__))
-#else
-# define _GL_ATTRIBUTE_ALWAYS_INLINE
+#ifndef _GL_ATTRIBUTE_ALWAYS_INLINE
+# if _GL_HAS_ATTRIBUTE (always_inline)
+# define _GL_ATTRIBUTE_ALWAYS_INLINE __attribute__ ((__always_inline__))
+# else
+# define _GL_ATTRIBUTE_ALWAYS_INLINE
+# endif
#endif
/* _GL_ATTRIBUTE_ARTIFICIAL declares that the function is not important to show
in stack traces when debugging. The compiler should omit the function from
stack traces. */
/* Applies to: function. */
-#if _GL_HAS_ATTRIBUTE (artificial)
-# define _GL_ATTRIBUTE_ARTIFICIAL __attribute__ ((__artificial__))
-#else
-# define _GL_ATTRIBUTE_ARTIFICIAL
+#ifndef _GL_ATTRIBUTE_ARTIFICIAL
+# if _GL_HAS_ATTRIBUTE (artificial)
+# define _GL_ATTRIBUTE_ARTIFICIAL __attribute__ ((__artificial__))
+# else
+# define _GL_ATTRIBUTE_ARTIFICIAL
+# endif
#endif
/* _GL_ATTRIBUTE_COLD declares that the function is rarely executed. */
/* Avoid __attribute__ ((cold)) on MinGW; see thread starting at
<https://lists.gnu.org/r/emacs-devel/2019-04/msg01152.html>.
Also, Oracle Studio 12.6 requires 'cold' not '__cold__'. */
-#if _GL_HAS_ATTRIBUTE (cold) && !defined __MINGW32__
-# ifndef __SUNPRO_C
-# define _GL_ATTRIBUTE_COLD __attribute__ ((__cold__))
+#ifndef _GL_ATTRIBUTE_COLD
+# if _GL_HAS_ATTRIBUTE (cold) && !defined __MINGW32__
+# ifndef __SUNPRO_C
+# define _GL_ATTRIBUTE_COLD __attribute__ ((__cold__))
+# else
+# define _GL_ATTRIBUTE_COLD __attribute__ ((cold))
+# endif
# else
-# define _GL_ATTRIBUTE_COLD __attribute__ ((cold))
+# define _GL_ATTRIBUTE_COLD
# endif
-#else
-# define _GL_ATTRIBUTE_COLD
#endif
/* _GL_ATTRIBUTE_CONST declares that it is OK for a compiler to omit duplicate
forever, and does not call longjmp.
(This attribute is stricter than _GL_ATTRIBUTE_PURE.) */
/* Applies to: functions. */
-#if _GL_HAS_ATTRIBUTE (const)
-# define _GL_ATTRIBUTE_CONST __attribute__ ((__const__))
-#else
-# define _GL_ATTRIBUTE_CONST
+#ifndef _GL_ATTRIBUTE_CONST
+# if _GL_HAS_ATTRIBUTE (const)
+# define _GL_ATTRIBUTE_CONST __attribute__ ((__const__))
+# else
+# define _GL_ATTRIBUTE_CONST
+# endif
#endif
/* _GL_ATTRIBUTE_DEALLOC (F, I) declares that the function returns pointers
_GL_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. */
-#if _GL_GNUC_PREREQ (11, 0)
-# define _GL_ATTRIBUTE_DEALLOC(f, i) __attribute__ ((__malloc__ (f, i)))
-#else
-# define _GL_ATTRIBUTE_DEALLOC(f, i)
+#ifndef _GL_ATTRIBUTE_DEALLOC
+# if _GL_GNUC_PREREQ (11, 0)
+# define _GL_ATTRIBUTE_DEALLOC(f, i) __attribute__ ((__malloc__ (f, i)))
+# else
+# define _GL_ATTRIBUTE_DEALLOC(f, i)
+# endif
#endif
/* If gnulib's <string.h> or <wchar.h> has already defined this macro, continue
to use this earlier definition, since <stdlib.h> may not have been included
- enumeration, enumeration item,
- typedef,
in C++ also: namespace, class, template specialization. */
-#ifdef __has_c_attribute
-# if __has_c_attribute (__deprecated__)
-# define _GL_ATTRIBUTE_DEPRECATED [[__deprecated__]]
-# endif
-#endif
-#if !defined _GL_ATTRIBUTE_DEPRECATED && _GL_HAS_ATTRIBUTE (deprecated)
-# define _GL_ATTRIBUTE_DEPRECATED __attribute__ ((__deprecated__))
-#endif
#ifndef _GL_ATTRIBUTE_DEPRECATED
-# define _GL_ATTRIBUTE_DEPRECATED
+# ifdef __has_c_attribute
+# if __has_c_attribute (__deprecated__)
+# define _GL_ATTRIBUTE_DEPRECATED [[__deprecated__]]
+# endif
+# endif
+# if !defined _GL_ATTRIBUTE_DEPRECATED && _GL_HAS_ATTRIBUTE (deprecated)
+# define _GL_ATTRIBUTE_DEPRECATED __attribute__ ((__deprecated__))
+# endif
+# ifndef _GL_ATTRIBUTE_DEPRECATED
+# define _GL_ATTRIBUTE_DEPRECATED
+# endif
#endif
/* _GL_ATTRIBUTE_ERROR(msg) requests an error if a function is called and
_GL_ATTRIBUTE_WARNING(msg) requests a warning if a function is called and
the function call is not optimized away. */
/* Applies to: functions. */
-#if _GL_HAS_ATTRIBUTE (error)
-# define _GL_ATTRIBUTE_ERROR(msg) __attribute__ ((__error__ (msg)))
-# define _GL_ATTRIBUTE_WARNING(msg) __attribute__ ((__warning__ (msg)))
-#elif _GL_HAS_ATTRIBUTE (diagnose_if)
-# define _GL_ATTRIBUTE_ERROR(msg) __attribute__ ((__diagnose_if__ (1, msg, "error")))
-# define _GL_ATTRIBUTE_WARNING(msg) __attribute__ ((__diagnose_if__ (1, msg, "warning")))
-#else
-# define _GL_ATTRIBUTE_ERROR(msg)
-# define _GL_ATTRIBUTE_WARNING(msg)
+#if !(defined _GL_ATTRIBUTE_ERROR && defined _GL_ATTRIBUTE_WARNING)
+# if _GL_HAS_ATTRIBUTE (error)
+# define _GL_ATTRIBUTE_ERROR(msg) __attribute__ ((__error__ (msg)))
+# define _GL_ATTRIBUTE_WARNING(msg) __attribute__ ((__warning__ (msg)))
+# elif _GL_HAS_ATTRIBUTE (diagnose_if)
+# define _GL_ATTRIBUTE_ERROR(msg) __attribute__ ((__diagnose_if__ (1, msg, "error")))
+# define _GL_ATTRIBUTE_WARNING(msg) __attribute__ ((__diagnose_if__ (1, msg, "warning")))
+# else
+# define _GL_ATTRIBUTE_ERROR(msg)
+# define _GL_ATTRIBUTE_WARNING(msg)
+# endif
#endif
/* _GL_ATTRIBUTE_EXTERNALLY_VISIBLE declares that the entity should remain
visible to debuggers etc., even with '-fwhole-program'. */
/* Applies to: functions, variables. */
-#if _GL_HAS_ATTRIBUTE (externally_visible)
-# define _GL_ATTRIBUTE_EXTERNALLY_VISIBLE __attribute__ ((externally_visible))
-#else
-# define _GL_ATTRIBUTE_EXTERNALLY_VISIBLE
+#ifndef _GL_ATTRIBUTE_EXTERNALLY_VISIBLE
+# if _GL_HAS_ATTRIBUTE (externally_visible)
+# define _GL_ATTRIBUTE_EXTERNALLY_VISIBLE __attribute__ ((externally_visible))
+# else
+# define _GL_ATTRIBUTE_EXTERNALLY_VISIBLE
+# endif
#endif
/* _GL_ATTRIBUTE_FALLTHROUGH declares that it is not a programming mistake if
'default' label. The compiler should not warn in this case. */
/* Applies to: Empty statement (;), inside a 'switch' statement. */
/* Always expands to something. */
-#ifdef __has_c_attribute
-# if __has_c_attribute (__fallthrough__)
-# define _GL_ATTRIBUTE_FALLTHROUGH [[__fallthrough__]]
-# endif
-#endif
-#if !defined _GL_ATTRIBUTE_FALLTHROUGH && _GL_HAS_ATTRIBUTE (fallthrough)
-# define _GL_ATTRIBUTE_FALLTHROUGH __attribute__ ((__fallthrough__))
-#endif
#ifndef _GL_ATTRIBUTE_FALLTHROUGH
-# define _GL_ATTRIBUTE_FALLTHROUGH ((void) 0)
+# ifdef __has_c_attribute
+# if __has_c_attribute (__fallthrough__)
+# define _GL_ATTRIBUTE_FALLTHROUGH [[__fallthrough__]]
+# endif
+# endif
+# if !defined _GL_ATTRIBUTE_FALLTHROUGH && _GL_HAS_ATTRIBUTE (fallthrough)
+# define _GL_ATTRIBUTE_FALLTHROUGH __attribute__ ((__fallthrough__))
+# endif
+# ifndef _GL_ATTRIBUTE_FALLTHROUGH
+# define _GL_ATTRIBUTE_FALLTHROUGH ((void) 0)
+# endif
#endif
/* _GL_ATTRIBUTE_FORMAT ((ARCHETYPE, STRING-INDEX, FIRST-TO-CHECK))
If FIRST-TO-CHECK is not 0, arguments starting at FIRST-TO_CHECK
are suitable for the format string. */
/* Applies to: functions. */
-#if _GL_HAS_ATTRIBUTE (format)
-# define _GL_ATTRIBUTE_FORMAT(spec) __attribute__ ((__format__ spec))
-#else
-# define _GL_ATTRIBUTE_FORMAT(spec)
+#ifndef _GL_ATTRIBUTE_FORMAT
+# if _GL_HAS_ATTRIBUTE (format)
+# define _GL_ATTRIBUTE_FORMAT(spec) __attribute__ ((__format__ spec))
+# else
+# define _GL_ATTRIBUTE_FORMAT(spec)
+# endif
#endif
/* _GL_ATTRIBUTE_LEAF declares that if the function is called from some other
exception handling. This declaration lets the compiler optimize that unit
more aggressively. */
/* Applies to: functions. */
-#if _GL_HAS_ATTRIBUTE (leaf)
-# define _GL_ATTRIBUTE_LEAF __attribute__ ((__leaf__))
-#else
-# define _GL_ATTRIBUTE_LEAF
+#ifndef _GL_ATTRIBUTE_LEAF
+# if _GL_HAS_ATTRIBUTE (leaf)
+# define _GL_ATTRIBUTE_LEAF __attribute__ ((__leaf__))
+# else
+# define _GL_ATTRIBUTE_LEAF
+# endif
#endif
/* _GL_ATTRIBUTE_MALLOC declares that the function returns a pointer to freshly
allocated memory. */
/* Applies to: functions. */
-#if _GL_HAS_ATTRIBUTE (malloc)
-# define _GL_ATTRIBUTE_MALLOC __attribute__ ((__malloc__))
-#else
-# define _GL_ATTRIBUTE_MALLOC
+#ifndef _GL_ATTRIBUTE_MALLOC
+# if _GL_HAS_ATTRIBUTE (malloc)
+# define _GL_ATTRIBUTE_MALLOC __attribute__ ((__malloc__))
+# else
+# define _GL_ATTRIBUTE_MALLOC
+# endif
#endif
/* _GL_ATTRIBUTE_MAY_ALIAS declares that pointers to the type may point to the
strict aliasing optimization. */
/* Applies to: types. */
/* Oracle Studio 12.6 mishandles may_alias despite __has_attribute OK. */
-#if _GL_HAS_ATTRIBUTE (may_alias) && !defined __SUNPRO_C
-# define _GL_ATTRIBUTE_MAY_ALIAS __attribute__ ((__may_alias__))
-#else
-# define _GL_ATTRIBUTE_MAY_ALIAS
+#ifndef _GL_ATTRIBUTE_MAY_ALIAS
+# if _GL_HAS_ATTRIBUTE (may_alias) && !defined __SUNPRO_C
+# define _GL_ATTRIBUTE_MAY_ALIAS __attribute__ ((__may_alias__))
+# else
+# define _GL_ATTRIBUTE_MAY_ALIAS
+# endif
#endif
/* _GL_ATTRIBUTE_MAYBE_UNUSED declares that it is not a programming mistake if
/* In C++ and C23, this is spelled [[__maybe_unused__]].
GCC's syntax is __attribute__ ((__unused__)).
clang supports both syntaxes. */
-#ifdef __has_c_attribute
-# if __has_c_attribute (__maybe_unused__)
-# define _GL_ATTRIBUTE_MAYBE_UNUSED [[__maybe_unused__]]
-# endif
-#endif
#ifndef _GL_ATTRIBUTE_MAYBE_UNUSED
-# define _GL_ATTRIBUTE_MAYBE_UNUSED _GL_ATTRIBUTE_UNUSED
+# ifdef __has_c_attribute
+# if __has_c_attribute (__maybe_unused__)
+# define _GL_ATTRIBUTE_MAYBE_UNUSED [[__maybe_unused__]]
+# endif
+# endif
+# ifndef _GL_ATTRIBUTE_MAYBE_UNUSED
+# define _GL_ATTRIBUTE_MAYBE_UNUSED _GL_ATTRIBUTE_UNUSED
+# endif
#endif
/* Alternative spelling of this macro, for convenience and for
compatibility with glibc/include/libc-symbols.h. */
discard the return value. The compiler may warn if the caller does not use
the return value, unless the caller uses something like ignore_value. */
/* Applies to: function, enumeration, class. */
-#ifdef __has_c_attribute
-# if __has_c_attribute (__nodiscard__)
-# define _GL_ATTRIBUTE_NODISCARD [[__nodiscard__]]
-# endif
-#endif
-#if !defined _GL_ATTRIBUTE_NODISCARD && _GL_HAS_ATTRIBUTE (warn_unused_result)
-# define _GL_ATTRIBUTE_NODISCARD __attribute__ ((__warn_unused_result__))
-#endif
#ifndef _GL_ATTRIBUTE_NODISCARD
-# define _GL_ATTRIBUTE_NODISCARD
+# ifdef __has_c_attribute
+# if __has_c_attribute (__nodiscard__)
+# define _GL_ATTRIBUTE_NODISCARD [[__nodiscard__]]
+# endif
+# endif
+# if !defined _GL_ATTRIBUTE_NODISCARD && _GL_HAS_ATTRIBUTE (warn_unused_result)
+# define _GL_ATTRIBUTE_NODISCARD __attribute__ ((__warn_unused_result__))
+# endif
+# ifndef _GL_ATTRIBUTE_NODISCARD
+# define _GL_ATTRIBUTE_NODISCARD
+# endif
#endif
/* _GL_ATTRIBUTE_NOINLINE tells that the compiler should not inline the
function. */
/* Applies to: functions. */
-#if _GL_HAS_ATTRIBUTE (noinline)
-# define _GL_ATTRIBUTE_NOINLINE __attribute__ ((__noinline__))
-#else
-# define _GL_ATTRIBUTE_NOINLINE
+#ifndef _GL_ATTRIBUTE_NOINLINE
+# if _GL_HAS_ATTRIBUTE (noinline)
+# define _GL_ATTRIBUTE_NOINLINE __attribute__ ((__noinline__))
+# else
+# define _GL_ATTRIBUTE_NOINLINE
+# endif
#endif
/* _GL_ATTRIBUTE_NONNULL ((N1, N2,...)) declares that the arguments N1, N2,...
_GL_ATTRIBUTE_NONNULL () declares that all pointer arguments must not be
null. */
/* Applies to: functions. */
-#if _GL_HAS_ATTRIBUTE (nonnull)
-# define _GL_ATTRIBUTE_NONNULL(args) __attribute__ ((__nonnull__ args))
-#else
-# define _GL_ATTRIBUTE_NONNULL(args)
+#ifndef _GL_ATTRIBUTE_NONNULL
+# if _GL_HAS_ATTRIBUTE (nonnull)
+# define _GL_ATTRIBUTE_NONNULL(args) __attribute__ ((__nonnull__ args))
+# else
+# define _GL_ATTRIBUTE_NONNULL(args)
+# endif
#endif
/* _GL_ATTRIBUTE_NONSTRING declares that 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'. */
-#if _GL_HAS_ATTRIBUTE (nonstring)
-# define _GL_ATTRIBUTE_NONSTRING __attribute__ ((__nonstring__))
-#else
-# define _GL_ATTRIBUTE_NONSTRING
+#ifndef _GL_ATTRIBUTE_NONSTRING
+# if _GL_HAS_ATTRIBUTE (nonstring)
+# define _GL_ATTRIBUTE_NONSTRING __attribute__ ((__nonstring__))
+# else
+# define _GL_ATTRIBUTE_NONSTRING
+# endif
#endif
/* There is no _GL_ATTRIBUTE_NORETURN; use _Noreturn instead. */
/* _GL_ATTRIBUTE_NOTHROW declares that the function does not throw exceptions.
*/
/* Applies to: functions. */
-#if _GL_HAS_ATTRIBUTE (nothrow) && !defined __cplusplus
-# define _GL_ATTRIBUTE_NOTHROW __attribute__ ((__nothrow__))
-#else
-# define _GL_ATTRIBUTE_NOTHROW
+#ifndef _GL_ATTRIBUTE_NOTHROW
+# if _GL_HAS_ATTRIBUTE (nothrow) && !defined __cplusplus
+# define _GL_ATTRIBUTE_NOTHROW __attribute__ ((__nothrow__))
+# else
+# define _GL_ATTRIBUTE_NOTHROW
+# endif
#endif
/* _GL_ATTRIBUTE_PACKED declares:
minimizing the memory required. */
/* Applies to: struct members, struct, union,
in C++ also: class. */
-#if _GL_HAS_ATTRIBUTE (packed)
-# define _GL_ATTRIBUTE_PACKED __attribute__ ((__packed__))
-#else
-# define _GL_ATTRIBUTE_PACKED
+#ifndef _GL_ATTRIBUTE_PACKED
+# if _GL_HAS_ATTRIBUTE (packed)
+# define _GL_ATTRIBUTE_PACKED __attribute__ ((__packed__))
+# else
+# define _GL_ATTRIBUTE_PACKED
+# endif
#endif
/* _GL_ATTRIBUTE_PURE declares that It is OK for a compiler to omit duplicate
observable state, and always returns exactly once.
(This attribute is looser than _GL_ATTRIBUTE_CONST.) */
/* Applies to: functions. */
-#if _GL_HAS_ATTRIBUTE (pure)
-# define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
-#else
-# define _GL_ATTRIBUTE_PURE
+#ifndef _GL_ATTRIBUTE_PURE
+# if _GL_HAS_ATTRIBUTE (pure)
+# define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
+# else
+# define _GL_ATTRIBUTE_PURE
+# endif
#endif
/* _GL_ATTRIBUTE_RETURNS_NONNULL declares that the function's return value is
a non-NULL pointer. */
/* Applies to: functions. */
-#if _GL_HAS_ATTRIBUTE (returns_nonnull)
-# define _GL_ATTRIBUTE_RETURNS_NONNULL __attribute__ ((__returns_nonnull__))
-#else
-# define _GL_ATTRIBUTE_RETURNS_NONNULL
+#ifndef _GL_ATTRIBUTE_RETURNS_NONNULL
+# if _GL_HAS_ATTRIBUTE (returns_nonnull)
+# define _GL_ATTRIBUTE_RETURNS_NONNULL __attribute__ ((__returns_nonnull__))
+# else
+# define _GL_ATTRIBUTE_RETURNS_NONNULL
+# endif
#endif
/* _GL_ATTRIBUTE_SENTINEL(pos) declares that the variadic function expects a
_GL_ATTRIBUTE_SENTINEL () - The last argument is NULL (requires C99).
_GL_ATTRIBUTE_SENTINEL ((N)) - The (N+1)st argument from the end is NULL. */
/* Applies to: functions. */
-#if _GL_HAS_ATTRIBUTE (sentinel)
-# define _GL_ATTRIBUTE_SENTINEL(pos) __attribute__ ((__sentinel__ pos))
-#else
-# define _GL_ATTRIBUTE_SENTINEL(pos)
+#ifndef _GL_ATTRIBUTE_SENTINEL
+# if _GL_HAS_ATTRIBUTE (sentinel)
+# define _GL_ATTRIBUTE_SENTINEL(pos) __attribute__ ((__sentinel__ pos))
+# else
+# define _GL_ATTRIBUTE_SENTINEL(pos)
+# endif
#endif
/* A helper macro. Don't use it directly. */
-#if _GL_HAS_ATTRIBUTE (unused)
-# define _GL_ATTRIBUTE_UNUSED __attribute__ ((__unused__))
-#else
-# define _GL_ATTRIBUTE_UNUSED
+#ifndef _GL_ATTRIBUTE_UNUSED
+# if _GL_HAS_ATTRIBUTE (unused)
+# define _GL_ATTRIBUTE_UNUSED __attribute__ ((__unused__))
+# else
+# define _GL_ATTRIBUTE_UNUSED
+# endif
#endif
]dnl There is no _GL_ATTRIBUTE_VISIBILITY; see m4/visibility.m4 instead.
/* Applies to: label (both in C and C++). */
/* Note that g++ < 4.5 does not support the '__attribute__ ((__unused__)) ;'
syntax. But clang does. */
-#if !(defined __cplusplus && !_GL_GNUC_PREREQ (4, 5)) || defined __clang__
-# define _GL_UNUSED_LABEL _GL_ATTRIBUTE_UNUSED
-#else
-# define _GL_UNUSED_LABEL
+#ifndef _GL_UNUSED_LABEL
+# if !(defined __cplusplus && !_GL_GNUC_PREREQ (4, 5)) || defined __clang__
+# define _GL_UNUSED_LABEL _GL_ATTRIBUTE_UNUSED
+# else
+# define _GL_UNUSED_LABEL
+# endif
#endif
])
AH_VERBATIM([async_safe],