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-rw-r--r--m4/gnulib-common.m474
1 files changed, 55 insertions, 19 deletions
diff --git a/m4/gnulib-common.m4 b/m4/gnulib-common.m4
index c84a2afd9c5..edb8572da25 100644
--- a/m4/gnulib-common.m4
+++ b/m4/gnulib-common.m4
@@ -1,4 +1,4 @@
-# gnulib-common.m4 serial 82
+# gnulib-common.m4 serial 86
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,
@@ -15,6 +15,10 @@ AC_DEFUN([gl_COMMON], [
AC_REQUIRE([gl_ZZGNULIB])
])
AC_DEFUN([gl_COMMON_BODY], [
+ AH_VERBATIM([0witness],
+[/* Witness that <config.h> has been included. */
+#define _GL_CONFIG_H_INCLUDED 1
+])
AH_VERBATIM([_GL_GNUC_PREREQ],
[/* True if the compiler says it groks GNU C version MAJOR.MINOR. */
#if defined __GNUC__ && defined __GNUC_MINOR__
@@ -116,6 +120,20 @@ AC_DEFUN([gl_COMMON_BODY], [
# pragma GCC diagnostic ignored "-Wpedantic"
#endif
+/* Define if, in a function declaration, the attributes in bracket syntax
+ [[...]] must come before the attributes in __attribute__((...)) syntax.
+ If this is defined, it is best to avoid the bracket syntax, so that the
+ various _GL_ATTRIBUTE_* can be cumulated on the same declaration in any
+ order. */
+#ifdef __cplusplus
+# if defined __clang__
+# define _GL_BRACKET_BEFORE_ATTRIBUTE 1
+# endif
+#else
+# if defined __GNUC__ && !defined __clang__
+# define _GL_BRACKET_BEFORE_ATTRIBUTE 1
+# endif
+#endif
]dnl There is no _GL_ATTRIBUTE_ALIGNED; use stdalign's alignas instead.
[
/* _GL_ATTRIBUTE_ALLOC_SIZE ((N)) declares that the Nth argument of the function
@@ -223,9 +241,11 @@ AC_DEFUN([gl_COMMON_BODY], [
- typedef,
in C++ also: namespace, class, template specialization. */
#ifndef _GL_ATTRIBUTE_DEPRECATED
-# ifdef __has_c_attribute
-# if __has_c_attribute (__deprecated__)
-# define _GL_ATTRIBUTE_DEPRECATED [[__deprecated__]]
+# ifndef _GL_BRACKET_BEFORE_ATTRIBUTE
+# ifdef __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)
@@ -355,13 +375,15 @@ AC_DEFUN([gl_COMMON_BODY], [
__has_c_attribute (__maybe_unused__) yields true but the use of
[[__maybe_unused__]] nevertheless produces a warning. */
#ifndef _GL_ATTRIBUTE_MAYBE_UNUSED
-# if defined __clang__ && defined __cplusplus
-# if !defined __apple_build_version__ && __clang_major__ >= 10
-# define _GL_ATTRIBUTE_MAYBE_UNUSED [[__maybe_unused__]]
-# endif
-# elif defined __has_c_attribute
-# if __has_c_attribute (__maybe_unused__)
-# define _GL_ATTRIBUTE_MAYBE_UNUSED [[__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 defined __has_c_attribute
+# if __has_c_attribute (__maybe_unused__)
+# define _GL_ATTRIBUTE_MAYBE_UNUSED [[__maybe_unused__]]
+# endif
# endif
# endif
# ifndef _GL_ATTRIBUTE_MAYBE_UNUSED
@@ -379,18 +401,20 @@ AC_DEFUN([gl_COMMON_BODY], [
the return value, unless the caller uses something like ignore_value. */
/* Applies to: function, enumeration, class. */
#ifndef _GL_ATTRIBUTE_NODISCARD
-# if defined __clang__ && defined __cplusplus
+# 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 defined __has_c_attribute
-# if __has_c_attribute (__nodiscard__)
-# define _GL_ATTRIBUTE_NODISCARD [[__nodiscard__]]
+# if __clang_major__ >= 1000
+# define _GL_ATTRIBUTE_NODISCARD [[__nodiscard__]]
+# endif
+# elif defined __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)
@@ -528,6 +552,18 @@ AC_DEFUN([gl_COMMON_BODY], [
# 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
@@ -583,7 +619,7 @@ AC_DEFUN([gl_COMMON_BODY], [
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}],
+ [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])