mirror of
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1a13c5e63e
* configure.ac: * src/conf_post.h: Remove workarounds now rendered redundant by Gnulib.
1730 lines
66 KiB
Plaintext
1730 lines
66 KiB
Plaintext
# gnulib-common.m4
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# serial 103
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dnl Copyright (C) 2007-2024 Free Software Foundation, Inc.
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dnl This file is free software; the Free Software Foundation
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dnl gives unlimited permission to copy and/or distribute it,
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dnl with or without modifications, as long as this notice is preserved.
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AC_PREREQ([2.62])
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# gl_COMMON
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# is expanded unconditionally through gnulib-tool magic.
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AC_DEFUN([gl_COMMON], [
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dnl Use AC_REQUIRE here, so that the code is expanded once only.
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AC_REQUIRE([gl_00GNULIB])
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AC_REQUIRE([gl_COMMON_BODY])
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AC_REQUIRE([gl_ZZGNULIB])
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])
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AC_DEFUN([gl_COMMON_BODY], [
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AH_VERBATIM([0witness],
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[/* Witness that <config.h> has been included. */
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#define _GL_CONFIG_H_INCLUDED 1
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])
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AH_VERBATIM([_GL_GNUC_PREREQ],
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[/* True if the compiler says it groks GNU C version MAJOR.MINOR.
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Except that
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- clang groks GNU C 4.2, even on Windows, where it does not define
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__GNUC__.
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- The OpenMandriva-modified clang compiler pretends that it groks
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GNU C version 13.1, but it doesn't: It does not support
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__attribute__ ((__malloc__ (f, i))), nor does it support
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__attribute__ ((__warning__ (message))) on a function redeclaration.
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- Users can make clang lie as well, through the -fgnuc-version option. */
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#if defined __GNUC__ && defined __GNUC_MINOR__ && !defined __clang__
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# define _GL_GNUC_PREREQ(major, minor) \
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((major) < __GNUC__ + ((minor) <= __GNUC_MINOR__))
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#elif defined __clang__
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/* clang really only groks GNU C 4.2. */
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# define _GL_GNUC_PREREQ(major, minor) \
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((major) < 4 + ((minor) <= 2))
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#else
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# define _GL_GNUC_PREREQ(major, minor) 0
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#endif
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])
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AH_VERBATIM([_Noreturn],
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[/* The _Noreturn keyword of C11. */
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#ifndef _Noreturn
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# if (defined __cplusplus \
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&& ((201103 <= __cplusplus && !(__GNUC__ == 4 && __GNUC_MINOR__ == 7)) \
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|| (defined _MSC_VER && 1900 <= _MSC_VER)) \
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&& 0)
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/* [[noreturn]] is not practically usable, because with it the syntax
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extern _Noreturn void func (...);
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would not be valid; such a declaration would only be valid with 'extern'
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and '_Noreturn' swapped, or without the 'extern' keyword. However, some
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AIX system header files and several gnulib header files use precisely
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this syntax with 'extern'. */
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# define _Noreturn [[noreturn]]
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# elif (defined __clang__ && __clang_major__ < 16 \
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&& defined _GL_WORK_AROUND_LLVM_BUG_59792)
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/* Compile with -D_GL_WORK_AROUND_LLVM_BUG_59792 to work around
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that rare LLVM bug, though you may get many false-alarm warnings. */
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# define _Noreturn
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# elif ((!defined __cplusplus || defined __clang__) \
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&& (201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) \
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|| (!defined __STRICT_ANSI__ \
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&& (_GL_GNUC_PREREQ (4, 7) \
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|| (defined __apple_build_version__ \
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? 6000000 <= __apple_build_version__ \
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: 3 < __clang_major__ + (5 <= __clang_minor__))))))
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/* _Noreturn works as-is. */
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# elif _GL_GNUC_PREREQ (2, 8) || defined __clang__ || 0x5110 <= __SUNPRO_C
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# define _Noreturn __attribute__ ((__noreturn__))
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# elif 1200 <= (defined _MSC_VER ? _MSC_VER : 0)
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# define _Noreturn __declspec (noreturn)
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# else
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# define _Noreturn
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# endif
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#endif
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])
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AH_VERBATIM([isoc99_inline],
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[/* Work around a bug in Apple GCC 4.0.1 build 5465: In C99 mode, it supports
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the ISO C 99 semantics of 'extern inline' (unlike the GNU C semantics of
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earlier versions), but does not display it by setting __GNUC_STDC_INLINE__.
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__APPLE__ && __MACH__ test for Mac OS X.
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__APPLE_CC__ tests for the Apple compiler and its version.
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__STDC_VERSION__ tests for the C99 mode. */
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#if defined __APPLE__ && defined __MACH__ && __APPLE_CC__ >= 5465 && !defined __cplusplus && __STDC_VERSION__ >= 199901L && !defined __GNUC_STDC_INLINE__
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# define __GNUC_STDC_INLINE__ 1
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#endif])
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AH_VERBATIM([attribute],
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[/* Attributes. */
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/* Define _GL_HAS_ATTRIBUTE only once, because on FreeBSD, with gcc < 5, if
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<config.h> gets included once again after <sys/cdefs.h>, __has_attribute(x)
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expands to 0 always, and redefining _GL_HAS_ATTRIBUTE would turn off all
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attributes. */
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#ifndef _GL_HAS_ATTRIBUTE
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# if (defined __has_attribute \
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&& (!defined __clang_minor__ \
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|| (defined __apple_build_version__ \
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? 7000000 <= __apple_build_version__ \
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: 5 <= __clang_major__)))
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# define _GL_HAS_ATTRIBUTE(attr) __has_attribute (__##attr##__)
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# else
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# define _GL_HAS_ATTRIBUTE(attr) _GL_ATTR_##attr
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# define _GL_ATTR_alloc_size _GL_GNUC_PREREQ (4, 3)
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# define _GL_ATTR_always_inline _GL_GNUC_PREREQ (3, 2)
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# define _GL_ATTR_artificial _GL_GNUC_PREREQ (4, 3)
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# define _GL_ATTR_cold _GL_GNUC_PREREQ (4, 3)
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# define _GL_ATTR_const _GL_GNUC_PREREQ (2, 95)
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# define _GL_ATTR_deprecated _GL_GNUC_PREREQ (3, 1)
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# define _GL_ATTR_diagnose_if 0
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# define _GL_ATTR_error _GL_GNUC_PREREQ (4, 3)
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# define _GL_ATTR_externally_visible _GL_GNUC_PREREQ (4, 1)
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# define _GL_ATTR_fallthrough _GL_GNUC_PREREQ (7, 0)
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# define _GL_ATTR_format _GL_GNUC_PREREQ (2, 7)
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# define _GL_ATTR_leaf _GL_GNUC_PREREQ (4, 6)
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# define _GL_ATTR_malloc _GL_GNUC_PREREQ (3, 0)
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# ifdef _ICC
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# define _GL_ATTR_may_alias 0
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# else
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# define _GL_ATTR_may_alias _GL_GNUC_PREREQ (3, 3)
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# endif
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# define _GL_ATTR_noinline _GL_GNUC_PREREQ (3, 1)
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# define _GL_ATTR_nonnull _GL_GNUC_PREREQ (3, 3)
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# define _GL_ATTR_nonstring _GL_GNUC_PREREQ (8, 0)
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# define _GL_ATTR_nothrow _GL_GNUC_PREREQ (3, 3)
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# define _GL_ATTR_packed _GL_GNUC_PREREQ (2, 7)
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# define _GL_ATTR_pure _GL_GNUC_PREREQ (2, 96)
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# define _GL_ATTR_reproducible 0 /* not yet supported, as of GCC 14 */
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# define _GL_ATTR_returns_nonnull _GL_GNUC_PREREQ (4, 9)
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# define _GL_ATTR_sentinel _GL_GNUC_PREREQ (4, 0)
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# define _GL_ATTR_unsequenced 0 /* not yet supported, as of GCC 14 */
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# define _GL_ATTR_unused _GL_GNUC_PREREQ (2, 7)
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# define _GL_ATTR_warn_unused_result _GL_GNUC_PREREQ (3, 4)
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# endif
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#endif
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/* Use __has_c_attribute if available. However, do not use with
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pre-C23 GCC, which can issue false positives if -Wpedantic. */
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#if (defined __has_c_attribute \
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&& ! (_GL_GNUC_PREREQ (4, 6) \
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&& (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) <= 201710))
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# define _GL_HAVE___HAS_C_ATTRIBUTE 1
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#else
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# define _GL_HAVE___HAS_C_ATTRIBUTE 0
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#endif
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/* Attributes in bracket syntax [[...]] vs. attributes in __attribute__((...))
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syntax, in function declarations. There are two problems here.
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(Last tested with gcc/g++ 14 and clang/clang++ 18.)
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1) We want that the _GL_ATTRIBUTE_* can be cumulated on the same declaration
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in any order.
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=========================== foo.c = foo.cc ===========================
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__attribute__ ((__deprecated__)) [[__nodiscard__]] int bar1 (int);
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[[__nodiscard__]] __attribute__ ((__deprecated__)) int bar2 (int);
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======================================================================
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This gives a syntax error
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- in C mode with gcc
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<https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108796>, and
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- in C++ mode with clang++ version < 16, and
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- in C++ mode, inside extern "C" {}, still in newer clang++ versions
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<https://github.com/llvm/llvm-project/issues/101990>.
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*/
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/* Define if, in a function declaration, the attributes in bracket syntax
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[[...]] must come before the attributes in __attribute__((...)) syntax.
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If this is defined, it is best to avoid the bracket syntax, so that the
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various _GL_ATTRIBUTE_* can be cumulated on the same declaration in any
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order. */
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#ifdef __cplusplus
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# if defined __clang__
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# define _GL_BRACKET_BEFORE_ATTRIBUTE 1
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# endif
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#else
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# if defined __GNUC__ && !defined __clang__
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# define _GL_BRACKET_BEFORE_ATTRIBUTE 1
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# endif
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#endif
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/*
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2) We want that the _GL_ATTRIBUTE_* can be placed in a declaration
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- without 'extern', in C as well as in C++,
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- with 'extern', in C,
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- with 'extern "C"', in C++
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in the same position. That is, we don't want to be forced to use a
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macro which arranges for the attribute to come before 'extern' in
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one case and after 'extern' in the other case, because such a macro
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would make the source code of .h files pretty ugly.
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=========================== foo.c = foo.cc ===========================
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#ifdef __cplusplus
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# define CC "C"
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#else
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# define CC
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#endif
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#define ND [[__nodiscard__]]
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#define WUR __attribute__((__warn_unused_result__))
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#ifdef __cplusplus
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extern "C" {
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#endif
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// gcc clang g++ clang++
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ND int foo (int);
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int ND foo (int); // warn error warn error
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int foo ND (int);
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int foo (int) ND; // warn error warn error
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WUR int foo (int);
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int WUR foo (int);
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int fo1 WUR (int); // error error error error
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int foo (int) WUR;
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#ifdef __cplusplus
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}
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#endif
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// gcc clang g++ clang++
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ND extern CC int foo (int); // error error
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extern CC ND int foo (int); // error error
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extern CC int ND foo (int); // warn error warn error
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extern CC int foo ND (int);
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extern CC int foo (int) ND; // warn error warn error
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WUR extern CC int foo (int); // warn
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extern CC WUR int foo (int);
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extern CC int WUR foo (int);
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extern CC int foo WUR (int); // error error error error
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extern CC int foo (int) WUR;
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ND EXTERN_C_FUNC int foo (int); // error error
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EXTERN_C_FUNC ND int foo (int);
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EXTERN_C_FUNC int ND foo (int); // warn error warn error
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EXTERN_C_FUNC int foo ND (int);
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EXTERN_C_FUNC int foo (int) ND; // warn error warn error
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WUR EXTERN_C_FUNC int foo (int); // warn
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EXTERN_C_FUNC WUR int foo (int);
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EXTERN_C_FUNC int WUR foo (int);
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EXTERN_C_FUNC int fo2 WUR (int); // error error error error
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EXTERN_C_FUNC int foo (int) WUR;
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======================================================================
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So, if we insist on using the 'extern' keyword ('extern CC' idiom):
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* If _GL_ATTRIBUTE_* expands to bracket syntax [[...]]
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in both C and C++, there is one available position:
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- between the function name and the parameter list.
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* If _GL_ATTRIBUTE_* expands to __attribute__((...)) syntax
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in both C and C++, there are several available positions:
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- before the return type,
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- between return type and function name,
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- at the end of the declaration.
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* If _GL_ATTRIBUTE_* expands to bracket syntax [[...]] in C and to
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__attribute__((...)) syntax in C++, there is no available position:
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it would need to come before 'extern' in C but after 'extern "C"'
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in C++.
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* If _GL_ATTRIBUTE_* expands to __attribute__((...)) syntax in C and
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to bracket syntax [[...]] in C++, there is one available position:
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- before the return type.
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Whereas, if we use the 'EXTERN_C_FUNC' idiom, which conditionally
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omits the 'extern' keyword:
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* If _GL_ATTRIBUTE_* expands to bracket syntax [[...]]
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in both C and C++, there are two available positions:
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- before the return type,
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- between the function name and the parameter list.
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* If _GL_ATTRIBUTE_* expands to __attribute__((...)) syntax
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in both C and C++, there are several available positions:
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- before the return type,
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- between return type and function name,
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- at the end of the declaration.
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* If _GL_ATTRIBUTE_* expands to bracket syntax [[...]] in C and to
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__attribute__((...)) syntax in C++, there is one available position:
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- before the return type.
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* If _GL_ATTRIBUTE_* expands to __attribute__((...)) syntax in C and
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to bracket syntax [[...]] in C++, there is one available position:
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- before the return type.
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The best choice is therefore to use the 'EXTERN_C_FUNC' idiom and
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put the attributes before the return type. This works regardless
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to what the _GL_ATTRIBUTE_* macros expand.
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*/
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/* Attributes in bracket syntax [[...]] vs. attributes in __attribute__((...))
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syntax, in static/inline function definitions.
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There are similar constraints as for function declarations. However, here,
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we cannot omit the storage-class specifier. Therefore, the following rule
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applies:
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* The macros
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_GL_ATTRIBUTE_CONST
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_GL_ATTRIBUTE_DEPRECATED
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_GL_ATTRIBUTE_MAYBE_UNUSED
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_GL_ATTRIBUTE_NODISCARD
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_GL_ATTRIBUTE_PURE
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_GL_ATTRIBUTE_REPRODUCIBLE
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_GL_ATTRIBUTE_UNSEQUENCED
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which may expand to bracket syntax [[...]], must come first, before the
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storage-class specifier.
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* Other _GL_ATTRIBUTE_* macros, that expand to __attribute__((...)) syntax,
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are better placed between the storage-class specifier and the return
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type.
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*/
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/* Attributes in bracket syntax [[...]] vs. attributes in __attribute__((...))
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syntax, in variable declarations.
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At which position can they be placed?
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(Last tested with gcc/g++ 14 and clang/clang++ 18.)
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=========================== foo.c = foo.cc ===========================
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#ifdef __cplusplus
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# define CC "C"
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#else
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# define CC
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#endif
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#define BD [[__deprecated__]]
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#define AD __attribute__ ((__deprecated__))
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// gcc clang g++ clang++
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BD extern CC int var; // error error
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extern CC BD int var; // error error
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extern CC int BD var; // warn error warn error
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extern CC int var BD;
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AD extern CC int var; // warn
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extern CC AD int var;
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extern CC int AD var;
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extern CC int var AD;
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BD extern CC int z[]; // error error
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extern CC BD int z[]; // error error
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extern CC int BD z[]; // warn error warn error
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extern CC int z1 BD [];
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extern CC int z[] BD; // warn error error
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AD extern CC int z[]; // warn
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extern CC AD int z[];
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extern CC int AD z[];
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extern CC int z2 AD []; // error error error error
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extern CC int z[] AD;
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======================================================================
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* For non-array variables, the only good position is after the variable name,
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that is, at the end of the declaration.
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* For array variables, you will need to distinguish C and C++:
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- In C, before the 'extern' keyword.
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- In C++, between the 'extern "C"' and the variable's type.
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*/
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]dnl There is no _GL_ATTRIBUTE_ALIGNED; use stdalign's alignas instead.
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[
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/* _GL_ATTRIBUTE_ALLOC_SIZE ((N)) declares that the Nth argument of the function
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is the size of the returned memory block.
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_GL_ATTRIBUTE_ALLOC_SIZE ((M, N)) declares that the Mth argument multiplied
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by the Nth argument of the function is the size of the returned memory block.
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*/
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/* Applies to: functions, pointer to functions, function types. */
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#ifndef _GL_ATTRIBUTE_ALLOC_SIZE
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# if _GL_HAS_ATTRIBUTE (alloc_size)
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# define _GL_ATTRIBUTE_ALLOC_SIZE(args) __attribute__ ((__alloc_size__ args))
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# else
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# define _GL_ATTRIBUTE_ALLOC_SIZE(args)
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# endif
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#endif
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/* _GL_ATTRIBUTE_ALWAYS_INLINE tells that the compiler should always inline the
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function and report an error if it cannot do so. */
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/* Applies to: functions. */
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#ifndef _GL_ATTRIBUTE_ALWAYS_INLINE
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# if _GL_HAS_ATTRIBUTE (always_inline)
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# define _GL_ATTRIBUTE_ALWAYS_INLINE __attribute__ ((__always_inline__))
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# else
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# define _GL_ATTRIBUTE_ALWAYS_INLINE
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# endif
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#endif
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/* _GL_ATTRIBUTE_ARTIFICIAL declares that the function is not important to show
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in stack traces when debugging. The compiler should omit the function from
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stack traces. */
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|
/* Applies to: functions. */
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|
#ifndef _GL_ATTRIBUTE_ARTIFICIAL
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# if _GL_HAS_ATTRIBUTE (artificial)
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# define _GL_ATTRIBUTE_ARTIFICIAL __attribute__ ((__artificial__))
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# else
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# define _GL_ATTRIBUTE_ARTIFICIAL
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# endif
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#endif
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|
/* _GL_ATTRIBUTE_COLD declares that the function is rarely executed. */
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|
/* Applies to: functions. */
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|
/* Avoid __attribute__ ((cold)) on MinGW; see thread starting at
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<https://lists.gnu.org/r/emacs-devel/2019-04/msg01152.html>.
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|
Also, Oracle Studio 12.6 requires 'cold' not '__cold__'. */
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|
#ifndef _GL_ATTRIBUTE_COLD
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# if _GL_HAS_ATTRIBUTE (cold) && !defined __MINGW32__
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# ifndef __SUNPRO_C
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# define _GL_ATTRIBUTE_COLD __attribute__ ((__cold__))
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# else
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# define _GL_ATTRIBUTE_COLD __attribute__ ((cold))
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# endif
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# else
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# define _GL_ATTRIBUTE_COLD
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# endif
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|
#endif
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/* _GL_ATTRIBUTE_CONST declares:
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|
It is OK for a compiler to move calls to the function and to omit
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calls to the function if another call has the same arguments or the
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result is not used.
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|
This attribute is safe for a function that neither depends on
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|
nor affects state, and always returns exactly once -
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e.g., does not raise an exception, call longjmp, or loop forever.
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|
(This attribute is stricter than _GL_ATTRIBUTE_PURE because the
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function cannot observe state. It is stricter than
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_GL_ATTRIBUTE_UNSEQUENCED because the function must return exactly
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once and cannot depend on state addressed by its arguments.) */
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|
/* Applies to: functions. */
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|
#ifndef _GL_ATTRIBUTE_CONST
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|
# if _GL_HAS_ATTRIBUTE (const)
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# define _GL_ATTRIBUTE_CONST __attribute__ ((__const__))
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# else
|
|
# define _GL_ATTRIBUTE_CONST _GL_ATTRIBUTE_UNSEQUENCED
|
|
# endif
|
|
#endif
|
|
|
|
/* _GL_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.
|
|
_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. */
|
|
#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
|
|
yet. */
|
|
#ifndef _GL_ATTRIBUTE_DEALLOC_FREE
|
|
# if defined __cplusplus && defined __GNUC__ && !defined __clang__
|
|
/* Work around GCC bug <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108231> */
|
|
# define _GL_ATTRIBUTE_DEALLOC_FREE \
|
|
_GL_ATTRIBUTE_DEALLOC ((void (*) (void *)) free, 1)
|
|
# else
|
|
# define _GL_ATTRIBUTE_DEALLOC_FREE \
|
|
_GL_ATTRIBUTE_DEALLOC (free, 1)
|
|
# endif
|
|
#endif
|
|
|
|
/* _GL_ATTRIBUTE_DEPRECATED: Declares that an entity is deprecated.
|
|
The compiler may 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. */
|
|
#ifndef _GL_ATTRIBUTE_DEPRECATED
|
|
# ifndef _GL_BRACKET_BEFORE_ATTRIBUTE
|
|
# if _GL_HAVE___HAS_C_ATTRIBUTE
|
|
# if __has_c_attribute (__deprecated__)
|
|
# define _GL_ATTRIBUTE_DEPRECATED [[__deprecated__]]
|
|
# endif
|
|
# 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
|
|
the function call is not optimized away.
|
|
_GL_ATTRIBUTE_WARNING(msg) requests a warning if a function is called and
|
|
the function call is not optimized away. */
|
|
/* Applies to: functions. */
|
|
#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. */
|
|
#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
|
|
the control flow falls through to the immediately following 'case' or
|
|
'default' label. The compiler should not warn in this case. */
|
|
/* Applies to: Empty statement (;), inside a 'switch' statement. */
|
|
/* Always expands to something. */
|
|
#ifndef _GL_ATTRIBUTE_FALLTHROUGH
|
|
# if _GL_HAVE___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))
|
|
declares that 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. */
|
|
#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
|
|
compilation unit, it executes code from that unit only by return or by
|
|
exception handling. This declaration lets the compiler optimize that unit
|
|
more aggressively. */
|
|
/* Applies to: functions. */
|
|
#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. */
|
|
#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
|
|
same storage as pointers to other types. Thus this declaration disables
|
|
strict aliasing optimization. */
|
|
/* Applies to: types. */
|
|
/* Oracle Studio 12.6 mishandles may_alias despite __has_attribute OK. */
|
|
#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
|
|
the entity is not used. The compiler should 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. */
|
|
/* In C++ and C23, this is spelled [[__maybe_unused__]].
|
|
GCC's syntax is __attribute__ ((__unused__)).
|
|
clang supports both syntaxes. Except that with clang ≥ 6, < 10, in C++ mode,
|
|
__has_c_attribute (__maybe_unused__) yields true but the use of
|
|
[[__maybe_unused__]] nevertheless produces a warning. */
|
|
#ifndef _GL_ATTRIBUTE_MAYBE_UNUSED
|
|
# ifndef _GL_BRACKET_BEFORE_ATTRIBUTE
|
|
# if defined __clang__ && defined __cplusplus
|
|
# if !defined __apple_build_version__ && __clang_major__ >= 10
|
|
# define _GL_ATTRIBUTE_MAYBE_UNUSED [[__maybe_unused__]]
|
|
# endif
|
|
# elif _GL_HAVE___HAS_C_ATTRIBUTE
|
|
# if __has_c_attribute (__maybe_unused__)
|
|
# define _GL_ATTRIBUTE_MAYBE_UNUSED [[__maybe_unused__]]
|
|
# endif
|
|
# 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. */
|
|
#define _GL_UNUSED _GL_ATTRIBUTE_MAYBE_UNUSED
|
|
/* Earlier spellings of this macro. */
|
|
#define _UNUSED_PARAMETER_ _GL_ATTRIBUTE_MAYBE_UNUSED
|
|
|
|
/* _GL_ATTRIBUTE_NODISCARD declares that the caller of the function should not
|
|
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. */
|
|
#ifndef _GL_ATTRIBUTE_NODISCARD
|
|
# ifndef _GL_BRACKET_BEFORE_ATTRIBUTE
|
|
# if defined __clang__ && defined __cplusplus
|
|
/* With clang up to 15.0.6 (at least), in C++ mode, [[__nodiscard__]] produces
|
|
a warning.
|
|
The 1000 below means a yet unknown threshold. When clang++ version X
|
|
starts supporting [[__nodiscard__]] without warning about it, you can
|
|
replace the 1000 with X. */
|
|
# if __clang_major__ >= 1000
|
|
# define _GL_ATTRIBUTE_NODISCARD [[__nodiscard__]]
|
|
# endif
|
|
# elif _GL_HAVE___HAS_C_ATTRIBUTE
|
|
# if __has_c_attribute (__nodiscard__)
|
|
# define _GL_ATTRIBUTE_NODISCARD [[__nodiscard__]]
|
|
# endif
|
|
# 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. */
|
|
#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,...
|
|
must not be NULL.
|
|
_GL_ATTRIBUTE_NONNULL () declares that all pointer arguments must not be
|
|
null. */
|
|
/* Applies to: functions. */
|
|
#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'. */
|
|
#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. */
|
|
/* After a function's parameter list, this attribute must come first, before
|
|
other attributes. */
|
|
#ifndef _GL_ATTRIBUTE_NOTHROW
|
|
# if defined __cplusplus
|
|
# if _GL_GNUC_PREREQ (2, 8) || __clang_major__ >= 4
|
|
# if __cplusplus >= 201103L
|
|
# define _GL_ATTRIBUTE_NOTHROW noexcept (true)
|
|
# else
|
|
# define _GL_ATTRIBUTE_NOTHROW throw ()
|
|
# endif
|
|
# else
|
|
# define _GL_ATTRIBUTE_NOTHROW
|
|
# endif
|
|
# else
|
|
# if _GL_HAS_ATTRIBUTE (nothrow)
|
|
# define _GL_ATTRIBUTE_NOTHROW __attribute__ ((__nothrow__))
|
|
# else
|
|
# define _GL_ATTRIBUTE_NOTHROW
|
|
# endif
|
|
# endif
|
|
#endif
|
|
|
|
/* _GL_ATTRIBUTE_PACKED declares:
|
|
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. */
|
|
#ifndef _GL_ATTRIBUTE_PACKED
|
|
/* Oracle Studio 12.6 miscompiles code with __attribute__ ((__packed__)) despite
|
|
__has_attribute OK. */
|
|
# if _GL_HAS_ATTRIBUTE (packed) && !defined __SUNPRO_C
|
|
# define _GL_ATTRIBUTE_PACKED __attribute__ ((__packed__))
|
|
# else
|
|
# define _GL_ATTRIBUTE_PACKED
|
|
# endif
|
|
#endif
|
|
|
|
/* _GL_ATTRIBUTE_PURE declares:
|
|
It is OK for a compiler to move calls to the function and to omit
|
|
calls to the function if another call has the same arguments or the
|
|
result is not used, and if observable state is the same.
|
|
This attribute is safe for a function that does not affect observable state
|
|
and always returns exactly once.
|
|
(This attribute is looser than _GL_ATTRIBUTE_CONST because the function
|
|
can depend on observable state. It is stricter than
|
|
_GL_ATTRIBUTE_REPRODUCIBLE because the function must return exactly
|
|
once and cannot affect state addressed by its arguments.) */
|
|
/* Applies to: functions. */
|
|
#ifndef _GL_ATTRIBUTE_PURE
|
|
# if _GL_HAS_ATTRIBUTE (pure)
|
|
# define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
|
|
# else
|
|
# define _GL_ATTRIBUTE_PURE _GL_ATTRIBUTE_REPRODUCIBLE
|
|
# endif
|
|
#endif
|
|
|
|
/* _GL_ATTRIBUTE_REPRODUCIBLE declares:
|
|
It is OK for a compiler to move calls to the function and to omit duplicate
|
|
calls to the function with the same arguments, so long as the state
|
|
addressed by its arguments is the same and is updated in time for
|
|
the rest of the program.
|
|
This attribute is safe for a function that is effectless and idempotent; see
|
|
ISO C 23 § 6.7.12.7 for a definition of these terms.
|
|
(This attribute is looser than _GL_ATTRIBUTE_UNSEQUENCED because
|
|
the function need not be stateless and idempotent. It is looser
|
|
than _GL_ATTRIBUTE_PURE because the function need not return
|
|
exactly once and can affect state addressed by its arguments.)
|
|
See also <https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2956.htm> and
|
|
<https://stackoverflow.com/questions/76847905/>. */
|
|
/* Applies to: functions, pointer to functions, function types. */
|
|
#ifndef _GL_ATTRIBUTE_REPRODUCIBLE
|
|
/* This may be revisited when gcc and clang support [[reproducible]] or possibly
|
|
__attribute__ ((__reproducible__)). */
|
|
# ifndef _GL_BRACKET_BEFORE_ATTRIBUTE
|
|
# if _GL_HAS_ATTRIBUTE (reproducible)
|
|
# define _GL_ATTRIBUTE_REPRODUCIBLE [[reproducible]]
|
|
# endif
|
|
# endif
|
|
# ifndef _GL_ATTRIBUTE_REPRODUCIBLE
|
|
# define _GL_ATTRIBUTE_REPRODUCIBLE
|
|
# endif
|
|
#endif
|
|
|
|
/* _GL_ATTRIBUTE_RETURNS_NONNULL declares that the function's return value is
|
|
a non-NULL pointer. */
|
|
/* Applies to: functions. */
|
|
#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
|
|
trailing NULL argument.
|
|
_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. */
|
|
#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
|
|
|
|
/* _GL_ATTRIBUTE_UNSEQUENCED declares:
|
|
It is OK for a compiler to move calls to the function and to omit duplicate
|
|
calls to the function with the same arguments, so long as the state
|
|
addressed by its arguments is the same.
|
|
This attribute is safe for a function that is effectless, idempotent,
|
|
stateless, and independent; see ISO C 23 § 6.7.12.7 for a definition of
|
|
these terms.
|
|
(This attribute is stricter than _GL_ATTRIBUTE_REPRODUCIBLE because
|
|
the function must be stateless and independent. It is looser than
|
|
_GL_ATTRIBUTE_CONST because the function need not return exactly
|
|
once and can depend on state addressed by its arguments.)
|
|
See also <https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2956.htm> and
|
|
<https://stackoverflow.com/questions/76847905/>. */
|
|
/* Applies to: functions, pointer to functions, function types. */
|
|
#ifndef _GL_ATTRIBUTE_UNSEQUENCED
|
|
/* This may be revisited when gcc and clang support [[unsequenced]] or possibly
|
|
__attribute__ ((__unsequenced__)). */
|
|
# ifndef _GL_BRACKET_BEFORE_ATTRIBUTE
|
|
# if _GL_HAS_ATTRIBUTE (unsequenced)
|
|
# define _GL_ATTRIBUTE_UNSEQUENCED [[unsequenced]]
|
|
# endif
|
|
# endif
|
|
# ifndef _GL_ATTRIBUTE_UNSEQUENCED
|
|
# define _GL_ATTRIBUTE_UNSEQUENCED
|
|
# endif
|
|
#endif
|
|
|
|
/* A helper macro. Don't use it directly. */
|
|
#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.
|
|
[
|
|
/* _GL_UNUSED_LABEL; declares that it is not a programming mistake if the
|
|
immediately preceding label is not used. The compiler should not warn
|
|
if the label is not used. */
|
|
/* Applies to: label (both in C and C++). */
|
|
/* Note that g++ < 4.5 does not support the '__attribute__ ((__unused__)) ;'
|
|
syntax. But clang does. */
|
|
#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([c_linkage],
|
|
[/* In C++, there is the concept of "language linkage", that encompasses
|
|
name mangling and function calling conventions.
|
|
The following macros start and end a block of "C" linkage. */
|
|
#ifdef __cplusplus
|
|
# define _GL_BEGIN_C_LINKAGE extern "C" {
|
|
# define _GL_END_C_LINKAGE }
|
|
#else
|
|
# define _GL_BEGIN_C_LINKAGE
|
|
# define _GL_END_C_LINKAGE
|
|
#endif
|
|
])
|
|
AH_VERBATIM([async_safe],
|
|
[/* The _GL_ASYNC_SAFE marker should be attached to functions that are
|
|
signal handlers (for signals other than SIGABRT, SIGPIPE) or can be
|
|
invoked from such signal handlers. Such functions have some restrictions:
|
|
* All functions that it calls should be marked _GL_ASYNC_SAFE as well,
|
|
or should be listed as async-signal-safe in POSIX
|
|
<https://pubs.opengroup.org/onlinepubs/9699919799/functions/V2_chap02.html#tag_15_04>
|
|
section 2.4.3. Note that malloc(), sprintf(), and fwrite(), in
|
|
particular, are NOT async-signal-safe.
|
|
* All memory locations (variables and struct fields) that these functions
|
|
access must be marked 'volatile'. This holds for both read and write
|
|
accesses. Otherwise the compiler might optimize away stores to and
|
|
reads from such locations that occur in the program, depending on its
|
|
data flow analysis. For example, when the program contains a loop
|
|
that is intended to inspect a variable set from within a signal handler
|
|
while (!signal_occurred)
|
|
;
|
|
the compiler is allowed to transform this into an endless loop if the
|
|
variable 'signal_occurred' is not declared 'volatile'.
|
|
Additionally, recall that:
|
|
* A signal handler should not modify errno (except if it is a handler
|
|
for a fatal signal and ends by raising the same signal again, thus
|
|
provoking the termination of the process). If it invokes a function
|
|
that may clobber errno, it needs to save and restore the value of
|
|
errno. */
|
|
#define _GL_ASYNC_SAFE
|
|
])
|
|
AH_VERBATIM([micro_optimizations],
|
|
[/* _GL_CMP (n1, n2) performs a three-valued comparison on n1 vs. n2, where
|
|
n1 and n2 are expressions without side effects, that evaluate to real
|
|
numbers (excluding NaN).
|
|
It returns
|
|
1 if n1 > n2
|
|
0 if n1 == n2
|
|
-1 if n1 < n2
|
|
The naïve code (n1 > n2 ? 1 : n1 < n2 ? -1 : 0) produces a conditional
|
|
jump with nearly all GCC versions up to GCC 10.
|
|
This variant (n1 < n2 ? -1 : n1 > n2) produces a conditional with many
|
|
GCC versions up to GCC 9.
|
|
The better code (n1 > n2) - (n1 < n2) from Hacker's Delight § 2-9
|
|
avoids conditional jumps in all GCC versions >= 3.4. */
|
|
#define _GL_CMP(n1, n2) (((n1) > (n2)) - ((n1) < (n2)))
|
|
])
|
|
dnl Hint which direction to take regarding cross-compilation guesses:
|
|
dnl When a user installs a program on a platform they are not intimately
|
|
dnl familiar with, --enable-cross-guesses=conservative is the appropriate
|
|
dnl choice. It implements the "If we don't know, assume the worst" principle.
|
|
dnl However, when an operating system developer (on a platform which is not
|
|
dnl yet known to gnulib) builds packages for their platform, they want to
|
|
dnl expose, not hide, possible platform bugs; in this case,
|
|
dnl --enable-cross-guesses=risky is the appropriate choice.
|
|
dnl Sets the variables
|
|
dnl gl_cross_guess_normal (to be used when 'yes' is good and 'no' is bad),
|
|
dnl gl_cross_guess_inverted (to be used when 'no' is good and 'yes' is bad).
|
|
AC_ARG_ENABLE([cross-guesses],
|
|
[AS_HELP_STRING([[--enable-cross-guesses={conservative|risky}]],
|
|
[specify policy for cross-compilation guesses])],
|
|
[if test "x$enableval" != xconservative && test "x$enableval" != xrisky; then
|
|
AC_MSG_WARN([invalid argument supplied to --enable-cross-guesses])
|
|
enableval=conservative
|
|
fi
|
|
gl_cross_guesses="$enableval"],
|
|
[gl_cross_guesses=conservative])
|
|
if test $gl_cross_guesses = risky; then
|
|
gl_cross_guess_normal="guessing yes"
|
|
gl_cross_guess_inverted="guessing no"
|
|
else
|
|
gl_cross_guess_normal="guessing no"
|
|
gl_cross_guess_inverted="guessing yes"
|
|
fi
|
|
dnl Preparation for running test programs:
|
|
dnl Tell glibc to write diagnostics from -D_FORTIFY_SOURCE=2 to stderr, not
|
|
dnl to /dev/tty, so they can be redirected to log files. Such diagnostics
|
|
dnl arise e.g., in the macros gl_PRINTF_DIRECTIVE_N, gl_SNPRINTF_DIRECTIVE_N.
|
|
LIBC_FATAL_STDERR_=1
|
|
export LIBC_FATAL_STDERR_
|
|
])
|
|
|
|
# gl_MODULE_INDICATOR_INIT_VARIABLE([variablename])
|
|
# gl_MODULE_INDICATOR_INIT_VARIABLE([variablename], [initialvalue])
|
|
# initializes the shell variable that indicates the presence of the given module
|
|
# as a C preprocessor expression.
|
|
AC_DEFUN([gl_MODULE_INDICATOR_INIT_VARIABLE],
|
|
[
|
|
GL_MODULE_INDICATOR_PREFIX[]_[$1]=m4_if([$2], , [0], [$2])
|
|
AC_SUBST(GL_MODULE_INDICATOR_PREFIX[]_[$1])
|
|
])
|
|
|
|
# gl_MODULE_INDICATOR_CONDITION
|
|
# expands to a C preprocessor expression that evaluates to 1 or 0, depending
|
|
# whether a gnulib module that has been requested shall be considered present
|
|
# or not.
|
|
m4_define([gl_MODULE_INDICATOR_CONDITION], [1])
|
|
|
|
# gl_MODULE_INDICATOR_SET_VARIABLE([modulename])
|
|
# sets the shell variable that indicates the presence of the given module to
|
|
# a C preprocessor expression that will evaluate to 1.
|
|
AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE],
|
|
[
|
|
gl_MODULE_INDICATOR_SET_VARIABLE_AUX(
|
|
[GL_MODULE_INDICATOR_PREFIX[]_GNULIB_[]m4_translit([[$1]],
|
|
[abcdefghijklmnopqrstuvwxyz./-],
|
|
[ABCDEFGHIJKLMNOPQRSTUVWXYZ___])],
|
|
[gl_MODULE_INDICATOR_CONDITION])
|
|
])
|
|
|
|
# gl_MODULE_INDICATOR_SET_VARIABLE_AUX([variable])
|
|
# modifies the shell variable to include the gl_MODULE_INDICATOR_CONDITION.
|
|
# The shell variable's value is a C preprocessor expression that evaluates
|
|
# to 0 or 1.
|
|
AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE_AUX],
|
|
[
|
|
m4_if(m4_defn([gl_MODULE_INDICATOR_CONDITION]), [1],
|
|
[
|
|
dnl Simplify the expression VALUE || 1 to 1.
|
|
$1=1
|
|
],
|
|
[gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR([$1],
|
|
[gl_MODULE_INDICATOR_CONDITION])])
|
|
])
|
|
|
|
# gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR([variable], [condition])
|
|
# modifies the shell variable to include the given condition. The shell
|
|
# variable's value is a C preprocessor expression that evaluates to 0 or 1.
|
|
AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR],
|
|
[
|
|
dnl Simplify the expression 1 || CONDITION to 1.
|
|
if test "$[]$1" != 1; then
|
|
dnl Simplify the expression 0 || CONDITION to CONDITION.
|
|
if test "$[]$1" = 0; then
|
|
$1=$2
|
|
else
|
|
$1="($[]$1 || $2)"
|
|
fi
|
|
fi
|
|
])
|
|
|
|
# gl_MODULE_INDICATOR([modulename])
|
|
# defines a C macro indicating the presence of the given module
|
|
# in a location where it can be used.
|
|
# | Value | Value |
|
|
# | in lib/ | in tests/ |
|
|
# --------------------------------------------+---------+-----------+
|
|
# Module present among main modules: | 1 | 1 |
|
|
# --------------------------------------------+---------+-----------+
|
|
# Module present among tests-related modules: | 0 | 1 |
|
|
# --------------------------------------------+---------+-----------+
|
|
# Module not present at all: | 0 | 0 |
|
|
# --------------------------------------------+---------+-----------+
|
|
AC_DEFUN([gl_MODULE_INDICATOR],
|
|
[
|
|
AC_DEFINE_UNQUOTED([GNULIB_]m4_translit([[$1]],
|
|
[abcdefghijklmnopqrstuvwxyz./-],
|
|
[ABCDEFGHIJKLMNOPQRSTUVWXYZ___]),
|
|
[gl_MODULE_INDICATOR_CONDITION],
|
|
[Define to a C preprocessor expression that evaluates to 1 or 0,
|
|
depending whether the gnulib module $1 shall be considered present.])
|
|
])
|
|
|
|
# gl_MODULE_INDICATOR_FOR_TESTS([modulename])
|
|
# defines a C macro indicating the presence of the given module
|
|
# in lib or tests. This is useful to determine whether the module
|
|
# should be tested.
|
|
# | Value | Value |
|
|
# | in lib/ | in tests/ |
|
|
# --------------------------------------------+---------+-----------+
|
|
# Module present among main modules: | 1 | 1 |
|
|
# --------------------------------------------+---------+-----------+
|
|
# Module present among tests-related modules: | 1 | 1 |
|
|
# --------------------------------------------+---------+-----------+
|
|
# Module not present at all: | 0 | 0 |
|
|
# --------------------------------------------+---------+-----------+
|
|
AC_DEFUN([gl_MODULE_INDICATOR_FOR_TESTS],
|
|
[
|
|
AC_DEFINE([GNULIB_TEST_]m4_translit([[$1]],
|
|
[abcdefghijklmnopqrstuvwxyz./-],
|
|
[ABCDEFGHIJKLMNOPQRSTUVWXYZ___]), [1],
|
|
[Define to 1 when the gnulib module $1 should be tested.])
|
|
])
|
|
|
|
# gl_ASSERT_NO_GNULIB_POSIXCHECK
|
|
# asserts that there will never be a need to #define GNULIB_POSIXCHECK.
|
|
# and thereby enables an optimization of configure and config.h.
|
|
# Used by Emacs.
|
|
AC_DEFUN([gl_ASSERT_NO_GNULIB_POSIXCHECK],
|
|
[
|
|
dnl Override gl_WARN_ON_USE_PREPARE.
|
|
dnl But hide this definition from 'aclocal'.
|
|
AC_DEFUN([gl_W][ARN_ON_USE_PREPARE], [])
|
|
])
|
|
|
|
# gl_ASSERT_NO_GNULIB_TESTS
|
|
# asserts that there will be no gnulib tests in the scope of the configure.ac
|
|
# and thereby enables an optimization of config.h.
|
|
# Used by Emacs.
|
|
AC_DEFUN([gl_ASSERT_NO_GNULIB_TESTS],
|
|
[
|
|
dnl Override gl_MODULE_INDICATOR_FOR_TESTS.
|
|
AC_DEFUN([gl_MODULE_INDICATOR_FOR_TESTS], [])
|
|
])
|
|
|
|
# Test whether <features.h> exists.
|
|
# Set HAVE_FEATURES_H.
|
|
AC_DEFUN([gl_FEATURES_H],
|
|
[
|
|
AC_CHECK_HEADERS_ONCE([features.h])
|
|
if test $ac_cv_header_features_h = yes; then
|
|
HAVE_FEATURES_H=1
|
|
else
|
|
HAVE_FEATURES_H=0
|
|
fi
|
|
AC_SUBST([HAVE_FEATURES_H])
|
|
])
|
|
|
|
# gl_PROG_CC_C99
|
|
# Modifies the value of the shell variable CC in an attempt to make $CC
|
|
# understand ISO C99 source code.
|
|
AC_DEFUN([gl_PROG_CC_C99],
|
|
[
|
|
dnl Just use AC_PROG_CC_C99.
|
|
dnl When AC_PROG_CC_C99 and AC_PROG_CC_STDC are used together, the substituted
|
|
dnl value of CC will contain the C99 enabling options twice. But this is only
|
|
dnl a cosmetic problem.
|
|
dnl With Autoconf >= 2.70, use AC_PROG_CC since it implies AC_PROG_CC_C99;
|
|
dnl this avoids a "warning: The macro `AC_PROG_CC_C99' is obsolete."
|
|
m4_version_prereq([2.70],
|
|
[AC_REQUIRE([AC_PROG_CC])],
|
|
[AC_REQUIRE([AC_PROG_CC_C99])])
|
|
])
|
|
|
|
# gl_PROG_AR_RANLIB
|
|
# Determines the values for AR, ARFLAGS, RANLIB that fit with the compiler.
|
|
# The user can set the variables AR, ARFLAGS, RANLIB if he wants to override
|
|
# the values.
|
|
AC_DEFUN([gl_PROG_AR_RANLIB],
|
|
[
|
|
dnl Minix 3 comes with two toolchains: The Amsterdam Compiler Kit compiler
|
|
dnl as "cc", and GCC as "gcc". They have different object file formats and
|
|
dnl library formats. In particular, the GNU binutils programs ar and ranlib
|
|
dnl produce libraries that work only with gcc, not with cc.
|
|
AC_REQUIRE([AC_PROG_CC])
|
|
dnl The '][' hides this use from 'aclocal'.
|
|
AC_BEFORE([$0], [A][M_PROG_AR])
|
|
AC_CACHE_CHECK([for Minix Amsterdam compiler], [gl_cv_c_amsterdam_compiler],
|
|
[
|
|
AC_EGREP_CPP([Amsterdam],
|
|
[
|
|
#ifdef __ACK__
|
|
Amsterdam
|
|
#endif
|
|
],
|
|
[gl_cv_c_amsterdam_compiler=yes],
|
|
[gl_cv_c_amsterdam_compiler=no])
|
|
])
|
|
|
|
dnl Don't compete with AM_PROG_AR's decision about AR/ARFLAGS if we are not
|
|
dnl building with __ACK__.
|
|
if test $gl_cv_c_amsterdam_compiler = yes; then
|
|
if test -z "$AR"; then
|
|
AR='cc -c.a'
|
|
fi
|
|
if test -z "$ARFLAGS"; then
|
|
ARFLAGS='-o'
|
|
fi
|
|
else
|
|
dnl AM_PROG_AR was added in automake v1.11.2. AM_PROG_AR does not AC_SUBST
|
|
dnl ARFLAGS variable (it is filed into Makefile.in directly by automake
|
|
dnl script on-demand, if not specified by ./configure of course).
|
|
dnl Don't AC_REQUIRE the AM_PROG_AR otherwise the code for __ACK__ above
|
|
dnl will be ignored. Also, pay attention to call AM_PROG_AR in else block
|
|
dnl because AM_PROG_AR is written so it could re-set AR variable even for
|
|
dnl __ACK__. It may seem like its easier to avoid calling the macro here,
|
|
dnl but we need to AC_SUBST both AR/ARFLAGS (thus those must have some good
|
|
dnl default value and automake should usually know them).
|
|
dnl
|
|
dnl The '][' hides this use from 'aclocal'.
|
|
m4_ifdef([A][M_PROG_AR], [A][M_PROG_AR], [:])
|
|
fi
|
|
|
|
dnl In case the code above has not helped with setting AR/ARFLAGS, use
|
|
dnl Automake-documented default values for AR and ARFLAGS, but prefer
|
|
dnl ${host}-ar over ar (useful for cross-compiling).
|
|
AC_CHECK_TOOL([AR], [ar], [ar])
|
|
if test -z "$ARFLAGS"; then
|
|
ARFLAGS='cr'
|
|
fi
|
|
|
|
AC_SUBST([AR])
|
|
AC_SUBST([ARFLAGS])
|
|
if test -z "$RANLIB"; then
|
|
if test $gl_cv_c_amsterdam_compiler = yes; then
|
|
RANLIB=':'
|
|
else
|
|
dnl Use the ranlib program if it is available.
|
|
AC_PROG_RANLIB
|
|
fi
|
|
fi
|
|
AC_SUBST([RANLIB])
|
|
])
|
|
|
|
# AC_C_RESTRICT
|
|
# This definition is copied from post-2.70 Autoconf and overrides the
|
|
# AC_C_RESTRICT macro from autoconf 2.60..2.70.
|
|
m4_version_prereq([2.70.1], [], [
|
|
AC_DEFUN([AC_C_RESTRICT],
|
|
[AC_CACHE_CHECK([for C/C++ restrict keyword], [ac_cv_c_restrict],
|
|
[ac_cv_c_restrict=no
|
|
# Put '__restrict__' first, to avoid problems with glibc and non-GCC; see:
|
|
# https://lists.gnu.org/archive/html/bug-autoconf/2016-02/msg00006.html
|
|
# Put 'restrict' last, because C++ lacks it.
|
|
for ac_kw in __restrict__ __restrict _Restrict restrict; do
|
|
AC_COMPILE_IFELSE(
|
|
[AC_LANG_PROGRAM(
|
|
[[typedef int *int_ptr;
|
|
int foo (int_ptr $ac_kw ip) { return ip[0]; }
|
|
int bar (int [$ac_kw]); /* Catch GCC bug 14050. */
|
|
int bar (int ip[$ac_kw]) { return ip[0]; }
|
|
]],
|
|
[[int s[1];
|
|
int *$ac_kw t = s;
|
|
t[0] = 0;
|
|
return foo (t) + bar (t);
|
|
]])],
|
|
[ac_cv_c_restrict=$ac_kw])
|
|
test "$ac_cv_c_restrict" != no && break
|
|
done
|
|
])
|
|
AH_VERBATIM([restrict],
|
|
[/* Define to the equivalent of the C99 'restrict' keyword, or to
|
|
nothing if this is not supported. Do not define if restrict is
|
|
supported only directly. */
|
|
#undef restrict
|
|
/* Work around a bug in older versions of Sun C++, which did not
|
|
#define __restrict__ or support _Restrict or __restrict__
|
|
even though the corresponding Sun C compiler ended up with
|
|
"#define restrict _Restrict" or "#define restrict __restrict__"
|
|
in the previous line. This workaround can be removed once
|
|
we assume Oracle Developer Studio 12.5 (2016) or later. */
|
|
#if defined __SUNPRO_CC && !defined __RESTRICT && !defined __restrict__
|
|
# define _Restrict
|
|
# define __restrict__
|
|
#endif])
|
|
case $ac_cv_c_restrict in
|
|
restrict) ;;
|
|
no) AC_DEFINE([restrict], []) ;;
|
|
*) AC_DEFINE_UNQUOTED([restrict], [$ac_cv_c_restrict]) ;;
|
|
esac
|
|
])# AC_C_RESTRICT
|
|
])
|
|
|
|
# gl_BIGENDIAN
|
|
# is like AC_C_BIGENDIAN, except that it can be AC_REQUIREd.
|
|
# Note that AC_REQUIRE([AC_C_BIGENDIAN]) does not work reliably because some
|
|
# macros invoke AC_C_BIGENDIAN with arguments.
|
|
AC_DEFUN([gl_BIGENDIAN],
|
|
[
|
|
AC_C_BIGENDIAN
|
|
])
|
|
|
|
# A temporary file descriptor.
|
|
# Must be less than 10, because dash 0.5.8 does not support redirections
|
|
# with multi-digit file descriptors.
|
|
m4_define([GL_TMP_FD], 9)
|
|
|
|
# gl_SILENT(command)
|
|
# executes command, but without the normal configure output.
|
|
# This is useful when you want to invoke AC_CACHE_CHECK (or AC_CHECK_FUNC etc.)
|
|
# inside another AC_CACHE_CHECK.
|
|
AC_DEFUN([gl_SILENT],
|
|
[
|
|
exec GL_TMP_FD>&AS_MESSAGE_FD AS_MESSAGE_FD>/dev/null
|
|
$1
|
|
exec AS_MESSAGE_FD>&GL_TMP_FD GL_TMP_FD>&-
|
|
])
|
|
|
|
# gl_CACHE_VAL_SILENT(cache-id, command-to-set-it)
|
|
# is like AC_CACHE_VAL(cache-id, command-to-set-it), except that it does not
|
|
# output a spurious "(cached)" mark in the midst of other configure output.
|
|
# This macro should be used instead of AC_CACHE_VAL when it is not surrounded
|
|
# by an AC_MSG_CHECKING/AC_MSG_RESULT pair.
|
|
AC_DEFUN([gl_CACHE_VAL_SILENT],
|
|
[
|
|
gl_SILENT([
|
|
AC_CACHE_VAL([$1], [$2])
|
|
])
|
|
])
|
|
|
|
# gl_CONDITIONAL(conditional, condition)
|
|
# is like AM_CONDITIONAL(conditional, condition), except that it does not
|
|
# produce an error
|
|
# configure: error: conditional "..." was never defined.
|
|
# Usually this means the macro was only invoked conditionally.
|
|
# when only invoked conditionally. Instead, in that case, both the _TRUE
|
|
# and the _FALSE case are disabled.
|
|
AC_DEFUN([gl_CONDITIONAL],
|
|
[
|
|
pushdef([AC_CONFIG_COMMANDS_PRE], [:])dnl
|
|
AM_CONDITIONAL([$1], [$2])
|
|
popdef([AC_CONFIG_COMMANDS_PRE])dnl
|
|
if test -z "${[$1]_TRUE}" && test -z "${[$1]_FALSE}"; then
|
|
[$1]_TRUE='#'
|
|
[$1]_FALSE='#'
|
|
fi
|
|
])
|
|
|
|
# gl_CC_ALLOW_WARNINGS
|
|
# sets and substitutes a variable GL_CFLAG_ALLOW_WARNINGS, to a $(CC) option
|
|
# that reverts a preceding '-Werror' option, if available.
|
|
# This is expected to be '-Wno-error' on gcc, clang (except clang/MSVC), xlclang
|
|
# and empty otherwise.
|
|
AC_DEFUN([gl_CC_ALLOW_WARNINGS],
|
|
[
|
|
AC_REQUIRE([AC_PROG_CC])
|
|
AC_CACHE_CHECK([for C compiler option to allow warnings],
|
|
[gl_cv_cc_wallow],
|
|
[rm -f conftest*
|
|
echo 'int dummy;' > conftest.c
|
|
AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -c conftest.c 2>conftest1.err]) >/dev/null
|
|
AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -Wno-error -c conftest.c 2>conftest2.err]) >/dev/null
|
|
dnl Test the number of error output lines, because AIX xlc accepts the
|
|
dnl option '-Wno-error', just to produce a warning
|
|
dnl "Option -Wno-error was incorrectly specified. The option will be ignored."
|
|
dnl afterwards.
|
|
if test $? = 0 && test `wc -l < conftest1.err` = `wc -l < conftest2.err`; then
|
|
gl_cv_cc_wallow='-Wno-error'
|
|
else
|
|
gl_cv_cc_wallow=none
|
|
fi
|
|
rm -f conftest*
|
|
])
|
|
case "$gl_cv_cc_wallow" in
|
|
none) GL_CFLAG_ALLOW_WARNINGS='' ;;
|
|
*) GL_CFLAG_ALLOW_WARNINGS="$gl_cv_cc_wallow" ;;
|
|
esac
|
|
AC_SUBST([GL_CFLAG_ALLOW_WARNINGS])
|
|
])
|
|
|
|
# gl_CXX_ALLOW_WARNINGS
|
|
# sets and substitutes a variable GL_CXXFLAG_ALLOW_WARNINGS, to a $(CC) option
|
|
# that reverts a preceding '-Werror' option, if available.
|
|
AC_DEFUN([gl_CXX_ALLOW_WARNINGS],
|
|
[
|
|
dnl Requires AC_PROG_CXX or gl_PROG_ANSI_CXX.
|
|
if test -n "$CXX" && test "$CXX" != no; then
|
|
AC_CACHE_CHECK([for C++ compiler option to allow warnings],
|
|
[gl_cv_cxx_wallow],
|
|
[rm -f conftest*
|
|
echo 'int dummy;' > conftest.cc
|
|
AC_TRY_COMMAND([${CXX-c++} $CXXFLAGS $CPPFLAGS -c conftest.cc 2>conftest1.err]) >/dev/null
|
|
AC_TRY_COMMAND([${CXX-c++} $CXXFLAGS $CPPFLAGS -Wno-error -c conftest.cc 2>conftest2.err]) >/dev/null
|
|
dnl Test the number of error output lines, because AIX xlC accepts the
|
|
dnl option '-Wno-error', just to produce a warning
|
|
dnl "Option -Wno-error was incorrectly specified. The option will be ignored."
|
|
dnl afterwards.
|
|
if test $? = 0 && test `wc -l < conftest1.err` = `wc -l < conftest2.err`; then
|
|
gl_cv_cxx_wallow='-Wno-error'
|
|
else
|
|
gl_cv_cxx_wallow=none
|
|
fi
|
|
rm -f conftest*
|
|
])
|
|
case "$gl_cv_cxx_wallow" in
|
|
none) GL_CXXFLAG_ALLOW_WARNINGS='' ;;
|
|
*) GL_CXXFLAG_ALLOW_WARNINGS="$gl_cv_cxx_wallow" ;;
|
|
esac
|
|
else
|
|
GL_CXXFLAG_ALLOW_WARNINGS=''
|
|
fi
|
|
AC_SUBST([GL_CXXFLAG_ALLOW_WARNINGS])
|
|
])
|
|
|
|
# gl_CC_GNULIB_WARNINGS
|
|
# sets and substitutes a variable GL_CFLAG_GNULIB_WARNINGS, to a $(CC) option
|
|
# set that enables or disables warnings as suitable for the Gnulib coding style.
|
|
AC_DEFUN([gl_CC_GNULIB_WARNINGS],
|
|
[
|
|
AC_REQUIRE([gl_CC_ALLOW_WARNINGS])
|
|
dnl Assume that the compiler supports -Wno-* options only if it also supports
|
|
dnl -Wno-error.
|
|
GL_CFLAG_GNULIB_WARNINGS=''
|
|
if test -n "$GL_CFLAG_ALLOW_WARNINGS"; then
|
|
dnl Enable these warning options:
|
|
dnl
|
|
dnl GCC clang
|
|
dnl -Wno-cast-qual >= 3 >= 3.9
|
|
dnl -Wno-conversion >= 3 >= 3.9
|
|
dnl -Wno-float-conversion >= 4.9 >= 3.9
|
|
dnl -Wno-float-equal >= 3 >= 3.9
|
|
dnl -Wimplicit-fallthrough >= 7 >= 3.9
|
|
dnl -Wno-pedantic >= 4.8 >= 3.9
|
|
dnl -Wno-sign-compare >= 3 >= 3.9
|
|
dnl -Wno-sign-conversion >= 4.3 >= 3.9
|
|
dnl -Wno-tautological-out-of-range-compare - >= 3.9
|
|
dnl -Wno-type-limits >= 4.3 >= 3.9
|
|
dnl -Wno-undef >= 3 >= 3.9
|
|
dnl -Wno-unsuffixed-float-constants >= 4.5
|
|
dnl -Wno-unused-function >= 3 >= 3.9
|
|
dnl -Wno-unused-parameter >= 3 >= 3.9
|
|
dnl
|
|
cat > conftest.c <<\EOF
|
|
#if (__GNUC__ >= 3 && !defined __clang__) || (__clang_major__ + (__clang_minor__ >= 9) > 3)
|
|
-Wno-cast-qual
|
|
-Wno-conversion
|
|
-Wno-float-equal
|
|
-Wno-sign-compare
|
|
-Wno-undef
|
|
-Wno-unused-function
|
|
-Wno-unused-parameter
|
|
#endif
|
|
#if (__GNUC__ + (__GNUC_MINOR__ >= 9) > 4 && !defined __clang__) || (__clang_major__ + (__clang_minor__ >= 9) > 3)
|
|
-Wno-float-conversion
|
|
#endif
|
|
#if (__GNUC__ >= 7 && !defined __clang__) || (__clang_major__ + (__clang_minor__ >= 9) > 3)
|
|
-Wimplicit-fallthrough
|
|
#endif
|
|
#if (__GNUC__ + (__GNUC_MINOR__ >= 8) > 4 && !defined __clang__) || (__clang_major__ + (__clang_minor__ >= 9) > 3)
|
|
-Wno-pedantic
|
|
#endif
|
|
#if 3 < __clang_major__ + (9 <= __clang_minor__)
|
|
-Wno-tautological-constant-out-of-range-compare
|
|
#endif
|
|
#if (__GNUC__ + (__GNUC_MINOR__ >= 3) > 4 && !defined __clang__) || (__clang_major__ + (__clang_minor__ >= 9) > 3)
|
|
-Wno-sign-conversion
|
|
-Wno-type-limits
|
|
#endif
|
|
#if (__GNUC__ + (__GNUC_MINOR__ >= 5) > 4 && !defined __clang__)
|
|
-Wno-unsuffixed-float-constants
|
|
#endif
|
|
EOF
|
|
gl_command="$CC $CFLAGS $CPPFLAGS -E conftest.c > conftest.out"
|
|
if AC_TRY_EVAL([gl_command]); then
|
|
gl_options=`grep -v '#' conftest.out`
|
|
for word in $gl_options; do
|
|
GL_CFLAG_GNULIB_WARNINGS="$GL_CFLAG_GNULIB_WARNINGS $word"
|
|
done
|
|
fi
|
|
rm -f conftest.c conftest.out
|
|
fi
|
|
AC_SUBST([GL_CFLAG_GNULIB_WARNINGS])
|
|
])
|
|
|
|
dnl gl_CONDITIONAL_HEADER([foo.h])
|
|
dnl takes a shell variable GL_GENERATE_FOO_H (with value true or false) as input
|
|
dnl and produces
|
|
dnl - an AC_SUBSTed variable FOO_H that is either a file name or empty, based
|
|
dnl on whether GL_GENERATE_FOO_H is true or false,
|
|
dnl - an Automake conditional GL_GENERATE_FOO_H that evaluates to the value of
|
|
dnl the shell variable GL_GENERATE_FOO_H.
|
|
AC_DEFUN([gl_CONDITIONAL_HEADER],
|
|
[
|
|
m4_pushdef([gl_header_name], AS_TR_SH(m4_toupper($1)))
|
|
m4_pushdef([gl_generate_var], [GL_GENERATE_]AS_TR_SH(m4_toupper($1)))
|
|
m4_pushdef([gl_generate_cond], [GL_GENERATE_]AS_TR_SH(m4_toupper($1)))
|
|
case "$gl_generate_var" in
|
|
false) gl_header_name='' ;;
|
|
true)
|
|
dnl It is OK to use a .h file in lib/ from within tests/, but not vice
|
|
dnl versa.
|
|
if test -z "$gl_header_name"; then
|
|
gl_header_name="${gl_source_base_prefix}$1"
|
|
fi
|
|
;;
|
|
*) echo "*** gl_generate_var is not set correctly" 1>&2; exit 1 ;;
|
|
esac
|
|
AC_SUBST(gl_header_name)
|
|
gl_CONDITIONAL(gl_generate_cond, [$gl_generate_var])
|
|
m4_popdef([gl_generate_cond])
|
|
m4_popdef([gl_generate_var])
|
|
m4_popdef([gl_header_name])
|
|
])
|
|
|
|
dnl Preparations for gl_CHECK_FUNCS_MACOS.
|
|
AC_DEFUN([gl_PREPARE_CHECK_FUNCS_MACOS],
|
|
[
|
|
AC_REQUIRE([AC_CANONICAL_HOST])
|
|
AC_REQUIRE([gl_COMPILER_CLANG])
|
|
AC_CACHE_CHECK([for compiler option needed when checking for future declarations],
|
|
[gl_cv_compiler_check_future_option],
|
|
[case "$host_os" in
|
|
dnl This is only needed on macOS.
|
|
darwin*)
|
|
if test $gl_cv_compiler_clang = yes; then
|
|
dnl Test whether the compiler supports the option
|
|
dnl '-Werror=unguarded-availability-new'.
|
|
saved_ac_compile="$ac_compile"
|
|
ac_compile="$ac_compile -Werror=unguarded-availability-new"
|
|
AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]],[[]])],
|
|
[gl_cv_compiler_check_future_option='-Werror=unguarded-availability-new'],
|
|
[gl_cv_compiler_check_future_option=none])
|
|
ac_compile="$saved_ac_compile"
|
|
else
|
|
gl_cv_compiler_check_future_option=none
|
|
fi
|
|
;;
|
|
*) gl_cv_compiler_check_future_option=none ;;
|
|
esac
|
|
])
|
|
])
|
|
|
|
dnl Pieces of the expansion of
|
|
dnl gl_CHECK_FUNCS_ANDROID
|
|
dnl gl_CHECK_FUNCS_MACOS
|
|
dnl gl_CHECK_FUNCS_ANDROID_MACOS
|
|
|
|
AC_DEFUN([gl_CHECK_FUNCS_DEFAULT_CASE],
|
|
[
|
|
*)
|
|
AC_CHECK_FUNC([$1])
|
|
[gl_cv_onwards_func_][$1]=$[ac_cv_func_][$1]
|
|
;;
|
|
])
|
|
|
|
AC_DEFUN([gl_CHECK_FUNCS_CASE_FOR_ANDROID],
|
|
[
|
|
linux*-android*)
|
|
AC_CHECK_DECL([$1], , , [$2])
|
|
if test $[ac_cv_have_decl_][$1] = yes; then
|
|
AC_CHECK_FUNC([[$1]])
|
|
if test $[ac_cv_func_][$1] = yes; then
|
|
[gl_cv_onwards_func_][$1]=yes
|
|
else
|
|
dnl The function is declared but does not exist. This should not
|
|
dnl happen normally. But anyway, we know that a future version
|
|
dnl of Android will have the function.
|
|
[gl_cv_onwards_func_][$1]='future OS version'
|
|
fi
|
|
else
|
|
[gl_cv_onwards_func_][$1]='future OS version'
|
|
fi
|
|
;;
|
|
])
|
|
|
|
AC_DEFUN([gl_CHECK_FUNCS_CASE_FOR_MACOS],
|
|
[
|
|
darwin*)
|
|
if test "x$gl_cv_compiler_check_future_option" != "xnone"; then
|
|
dnl Use a compile test, not a link test.
|
|
saved_ac_compile="$ac_compile"
|
|
ac_compile="$ac_compile $gl_cv_compiler_check_future_option"
|
|
saved_ac_compile_for_check_decl="$ac_compile_for_check_decl"
|
|
ac_compile_for_check_decl="$ac_compile_for_check_decl $gl_cv_compiler_check_future_option"
|
|
unset [ac_cv_have_decl_][$1]
|
|
AC_CHECK_DECL([$1], , , [$2])
|
|
ac_compile="$saved_ac_compile"
|
|
ac_compile_for_check_decl="$saved_ac_compile_for_check_decl"
|
|
[ac_cv_func_][$1]="$[ac_cv_have_decl_][$1]"
|
|
if test $[ac_cv_func_][$1] = yes; then
|
|
[gl_cv_onwards_func_][$1]=yes
|
|
else
|
|
unset [ac_cv_have_decl_][$1]
|
|
AC_CHECK_DECL([$1], , , [$2])
|
|
if test $[ac_cv_have_decl_][$1] = yes; then
|
|
[gl_cv_onwards_func_][$1]='future OS version'
|
|
else
|
|
[gl_cv_onwards_func_][$1]=no
|
|
fi
|
|
fi
|
|
else
|
|
AC_CHECK_FUNC([$1])
|
|
[gl_cv_onwards_func_][$1]=$[ac_cv_func_][$1]
|
|
fi
|
|
;;
|
|
])
|
|
|
|
AC_DEFUN([gl_CHECK_FUNCS_SET_RESULTS],
|
|
[
|
|
case "$[gl_cv_onwards_func_][$1]" in
|
|
future*) [ac_cv_func_][$1]=no ;;
|
|
*) [ac_cv_func_][$1]=$[gl_cv_onwards_func_][$1] ;;
|
|
esac
|
|
if test $[ac_cv_func_][$1] = yes; then
|
|
AC_DEFINE([HAVE_]m4_translit([[$1]],
|
|
[abcdefghijklmnopqrstuvwxyz],
|
|
[ABCDEFGHIJKLMNOPQRSTUVWXYZ]),
|
|
[1], [Define to 1 if you have the `$1' function.])
|
|
fi
|
|
])
|
|
|
|
dnl gl_CHECK_FUNCS_ANDROID([func], [[#include <foo.h>]])
|
|
dnl is like AC_CHECK_FUNCS([func]), taking into account a portability problem
|
|
dnl on Android.
|
|
dnl
|
|
dnl When code is compiled on Android, it is in the context of a certain
|
|
dnl "Android API level", which indicates the minimum version of Android on
|
|
dnl which the app can be installed. In other words, you don't compile for a
|
|
dnl specific version of Android. You compile for all versions of Android,
|
|
dnl onwards from the given API level.
|
|
dnl Thus, the question "does the OS have the function func" has three possible
|
|
dnl answers:
|
|
dnl - yes, in all versions starting from the given API level,
|
|
dnl - no, in no version,
|
|
dnl - not in the given API level, but in a later version of Android.
|
|
dnl
|
|
dnl In detail, this works as follows:
|
|
dnl If func was added to Android API level, say, 28, then the libc.so has the
|
|
dnl symbol func always, whereas the header file <foo.h> declares func
|
|
dnl conditionally:
|
|
dnl #if __ANDROID_API__ >= 28
|
|
dnl ... func (...) __INTRODUCED_IN(28);
|
|
dnl #endif
|
|
dnl Thus, when compiling with "clang -target armv7a-unknown-linux-android28",
|
|
dnl the function func is declared and exists in libc.
|
|
dnl Whereas when compiling with "clang -target armv7a-unknown-linux-android27",
|
|
dnl the function func is not declared but exists in libc.
|
|
dnl
|
|
dnl This macro sets two variables:
|
|
dnl - gl_cv_onwards_func_<func> to yes / no / "future OS version"
|
|
dnl - ac_cv_func_<func> to yes / no / no
|
|
dnl The first variable allows to distinguish all three cases.
|
|
dnl The second variable is set, so that an invocation
|
|
dnl gl_CHECK_FUNCS_ANDROID([func], [[#include <foo.h>]])
|
|
dnl can be used as a drop-in replacement for
|
|
dnl AC_CHECK_FUNCS([func]).
|
|
AC_DEFUN([gl_CHECK_FUNCS_ANDROID],
|
|
[
|
|
AC_REQUIRE([AC_CANONICAL_HOST])
|
|
AC_CACHE_CHECK([for [$1]],
|
|
[[gl_cv_onwards_func_][$1]],
|
|
[gl_SILENT([
|
|
case "$host_os" in
|
|
gl_CHECK_FUNCS_CASE_FOR_ANDROID([$1], [$2])
|
|
gl_CHECK_FUNCS_DEFAULT_CASE([$1])
|
|
esac
|
|
])
|
|
])
|
|
gl_CHECK_FUNCS_SET_RESULTS([$1])
|
|
])
|
|
|
|
dnl gl_CHECK_FUNCS_MACOS([func], [[#include <foo.h>]])
|
|
dnl is like AC_CHECK_FUNCS([func]), taking into account a portability problem
|
|
dnl on macOS.
|
|
dnl
|
|
dnl When code is compiled on macOS, it is in the context of a certain minimum
|
|
dnl macOS version, that can be set through the option '-mmacosx-version-min='.
|
|
dnl In other words, you don't compile for a specific version of macOS. You
|
|
dnl compile for all versions of macOS, onwards from the given version.
|
|
dnl Thus, the question "does the OS have the function func" has three possible
|
|
dnl answers:
|
|
dnl - yes, in all versions starting from the given version,
|
|
dnl - no, in no version,
|
|
dnl - not in the given version, but in a later version of macOS.
|
|
dnl
|
|
dnl In detail, this works as follows:
|
|
dnl If func was added to, say, macOS version 13, then the libc has the
|
|
dnl symbol func always, whereas the header file <foo.h> declares func
|
|
dnl conditionally with a special availability attribute:
|
|
dnl ... func (...) __attribute__((availability(macos,introduced=13.0)));
|
|
dnl Thus, when compiling with "clang mmacosx-version-min=13", there is no
|
|
dnl warning about the use of func, and the resulting binary
|
|
dnl - runs fine on macOS 13,
|
|
dnl - aborts with a dyld "Symbol not found" message on macOS 12.
|
|
dnl Whereas, when compiling with "clang mmacosx-version-min=12", there is a
|
|
dnl warning: 'func' is only available on macOS 13.0 or newer
|
|
dnl [-Wunguarded-availability-new],
|
|
dnl and the resulting binary
|
|
dnl - runs fine on macOS 13,
|
|
dnl - crashes with a SIGSEGV (signal 11) on macOS 12.
|
|
dnl
|
|
dnl This macro sets two variables:
|
|
dnl - gl_cv_onwards_func_<func> to yes / no / "future OS version"
|
|
dnl - ac_cv_func_<func> to yes / no / no
|
|
dnl The first variable allows to distinguish all three cases.
|
|
dnl The second variable is set, so that an invocation
|
|
dnl gl_CHECK_FUNCS_MACOS([func], [[#include <foo.h>]])
|
|
dnl can be used as a drop-in replacement for
|
|
dnl AC_CHECK_FUNCS([func]).
|
|
AC_DEFUN([gl_CHECK_FUNCS_MACOS],
|
|
[
|
|
AC_REQUIRE([AC_CANONICAL_HOST])
|
|
AC_REQUIRE([gl_PREPARE_CHECK_FUNCS_MACOS])
|
|
AC_CACHE_CHECK([for [$1]],
|
|
[[gl_cv_onwards_func_][$1]],
|
|
[gl_SILENT([
|
|
case "$host_os" in
|
|
gl_CHECK_FUNCS_CASE_FOR_MACOS([$1], [$2])
|
|
gl_CHECK_FUNCS_DEFAULT_CASE([$1])
|
|
esac
|
|
])
|
|
])
|
|
gl_CHECK_FUNCS_SET_RESULTS([$1])
|
|
])
|
|
|
|
dnl gl_CHECK_FUNCS_ANDROID_MACOS([func], [[#include <foo.h>]])
|
|
dnl is like AC_CHECK_FUNCS([func]), taking into account a portability problem
|
|
dnl on Android and on macOS.
|
|
dnl It is the combination of gl_CHECK_FUNCS_ANDROID and gl_CHECK_FUNCS_MACOS.
|
|
AC_DEFUN([gl_CHECK_FUNCS_ANDROID_MACOS],
|
|
[
|
|
AC_REQUIRE([AC_CANONICAL_HOST])
|
|
AC_REQUIRE([gl_PREPARE_CHECK_FUNCS_MACOS])
|
|
AC_CACHE_CHECK([for [$1]],
|
|
[[gl_cv_onwards_func_][$1]],
|
|
[gl_SILENT([
|
|
case "$host_os" in
|
|
gl_CHECK_FUNCS_CASE_FOR_ANDROID([$1], [$2])
|
|
gl_CHECK_FUNCS_CASE_FOR_MACOS([$1], [$2])
|
|
gl_CHECK_FUNCS_DEFAULT_CASE([$1])
|
|
esac
|
|
])
|
|
])
|
|
gl_CHECK_FUNCS_SET_RESULTS([$1])
|
|
])
|
|
|
|
dnl Expands to some code for use in .c programs that, on native Windows, defines
|
|
dnl the Microsoft deprecated alias function names to the underscore-prefixed
|
|
dnl actual function names. With this macro, these function names are available
|
|
dnl without linking with '-loldnames' and without generating warnings.
|
|
dnl Usage: Use it after all system header files are included.
|
|
dnl #include <...>
|
|
dnl #include <...>
|
|
dnl ]GL_MDA_DEFINES[
|
|
dnl ...
|
|
AC_DEFUN([GL_MDA_DEFINES],[
|
|
AC_REQUIRE([_GL_MDA_DEFINES])
|
|
[$gl_mda_defines]
|
|
])
|
|
AC_DEFUN([_GL_MDA_DEFINES],
|
|
[gl_mda_defines='
|
|
#if defined _WIN32 && !defined __CYGWIN__
|
|
#define access _access
|
|
#define chdir _chdir
|
|
#define chmod _chmod
|
|
#define close _close
|
|
#define creat _creat
|
|
#define dup _dup
|
|
#define dup2 _dup2
|
|
#define ecvt _ecvt
|
|
#define execl _execl
|
|
#define execle _execle
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#define execlp _execlp
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#define execv _execv
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#define execve _execve
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#define execvp _execvp
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#define execvpe _execvpe
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#define fcloseall _fcloseall
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#define fcvt _fcvt
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#define fdopen _fdopen
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#define fileno _fileno
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#define gcvt _gcvt
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#define getcwd _getcwd
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#define getpid _getpid
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#define getw _getw
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#define isatty _isatty
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#define j0 _j0
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#define j1 _j1
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#define jn _jn
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#define lfind _lfind
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#define lsearch _lsearch
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#define lseek _lseek
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#define memccpy _memccpy
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#define mkdir _mkdir
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#define mktemp _mktemp
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#define open _open
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#define putenv _putenv
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#define putw _putw
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#define read _read
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#define rmdir _rmdir
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#define strdup _strdup
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#define swab _swab
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#define tempnam _tempnam
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#define tzset _tzset
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#define umask _umask
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#define unlink _unlink
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#define utime _utime
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#define wcsdup _wcsdup
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#define write _write
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#define y0 _y0
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#define y1 _y1
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#define yn _yn
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#endif
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'
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])
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