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-rw-r--r--gnulib/import/m4/gnulib-common.m4411
1 files changed, 381 insertions, 30 deletions
diff --git a/gnulib/import/m4/gnulib-common.m4 b/gnulib/import/m4/gnulib-common.m4
index 535359b2cf6..30911d1581a 100644
--- a/gnulib/import/m4/gnulib-common.m4
+++ b/gnulib/import/m4/gnulib-common.m4
@@ -1,5 +1,5 @@
-# gnulib-common.m4 serial 63
-dnl Copyright (C) 2007-2021 Free Software Foundation, Inc.
+# gnulib-common.m4 serial 73
+dnl Copyright (C) 2007-2022 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
@@ -39,11 +39,12 @@ AC_DEFUN([gl_COMMON_BODY], [
this syntax with 'extern'. */
# define _Noreturn [[noreturn]]
# elif ((!defined __cplusplus || defined __clang__) \
- && (201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) \
- || _GL_GNUC_PREREQ (4, 7) \
- || (defined __apple_build_version__ \
- ? 6000000 <= __apple_build_version__ \
- : 3 < __clang_major__ + (5 <= __clang_minor__))))
+ && (201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) \
+ || (!defined __STRICT_ANSI__ \
+ && (_GL_GNUC_PREREQ (4, 7) \
+ || (defined __apple_build_version__ \
+ ? 6000000 <= __apple_build_version__ \
+ : 3 < __clang_major__ + (5 <= __clang_minor__))))))
/* _Noreturn works as-is. */
# elif _GL_GNUC_PREREQ (2, 8) || defined __clang__ || 0x5110 <= __SUNPRO_C
# define _Noreturn __attribute__ ((__noreturn__))
@@ -66,7 +67,11 @@ AC_DEFUN([gl_COMMON_BODY], [
#endif])
AH_VERBATIM([attribute],
[/* Attributes. */
-#ifdef __has_attribute
+#if (defined __has_attribute \
+ && (!defined __clang_minor__ \
+ || (defined __apple_build_version__ \
+ ? 6000000 <= __apple_build_version__ \
+ : 3 < __clang_major__ + (5 <= __clang_minor__))))
# define _GL_HAS_ATTRIBUTE(attr) __has_attribute (__##attr##__)
#else
# define _GL_HAS_ATTRIBUTE(attr) _GL_ATTR_##attr
@@ -82,12 +87,12 @@ AC_DEFUN([gl_COMMON_BODY], [
# define _GL_ATTR_fallthrough _GL_GNUC_PREREQ (7, 0)
# define _GL_ATTR_format _GL_GNUC_PREREQ (2, 7)
# define _GL_ATTR_leaf _GL_GNUC_PREREQ (4, 6)
+# define _GL_ATTR_malloc _GL_GNUC_PREREQ (3, 0)
# ifdef _ICC
# define _GL_ATTR_may_alias 0
# else
# define _GL_ATTR_may_alias _GL_GNUC_PREREQ (3, 3)
# endif
-# define _GL_ATTR_malloc _GL_GNUC_PREREQ (3, 0)
# define _GL_ATTR_noinline _GL_GNUC_PREREQ (3, 1)
# define _GL_ATTR_nonnull _GL_GNUC_PREREQ (3, 3)
# define _GL_ATTR_nonstring _GL_GNUC_PREREQ (8, 0)
@@ -100,26 +105,51 @@ AC_DEFUN([gl_COMMON_BODY], [
# define _GL_ATTR_warn_unused_result _GL_GNUC_PREREQ (3, 4)
#endif
+#ifdef __has_c_attribute
+# if ((defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) <= 201710 \
+ && _GL_GNUC_PREREQ (4, 6))
+# pragma GCC diagnostic ignored "-Wpedantic"
+# endif
+# define _GL_HAS_C_ATTRIBUTE(attr) __has_c_attribute (__##attr##__)
+#else
+# define _GL_HAS_C_ATTRIBUTE(attr) 0
+#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
+ is the size of the returned memory block.
+ _GL_ATTRIBUTE_ALLOC_SIZE ((M, N)) declares that the Mth argument multiplied
+ by the Nth argument of the function is the size of the returned memory block.
+ */
+/* Applies to: function, pointer to function, function types. */
#if _GL_HAS_ATTRIBUTE (alloc_size)
# define _GL_ATTRIBUTE_ALLOC_SIZE(args) __attribute__ ((__alloc_size__ args))
#else
# define _GL_ATTRIBUTE_ALLOC_SIZE(args)
#endif
+/* _GL_ATTRIBUTE_ALWAYS_INLINE tells that the compiler should always inline the
+ function and report an error if it cannot do so. */
+/* Applies to: function. */
#if _GL_HAS_ATTRIBUTE (always_inline)
# define _GL_ATTRIBUTE_ALWAYS_INLINE __attribute__ ((__always_inline__))
#else
# define _GL_ATTRIBUTE_ALWAYS_INLINE
#endif
+/* _GL_ATTRIBUTE_ARTIFICIAL declares that the function is not important to show
+ in stack traces when debugging. The compiler should omit the function from
+ stack traces. */
+/* Applies to: function. */
#if _GL_HAS_ATTRIBUTE (artificial)
# define _GL_ATTRIBUTE_ARTIFICIAL __attribute__ ((__artificial__))
#else
# define _GL_ATTRIBUTE_ARTIFICIAL
#endif
+/* _GL_ATTRIBUTE_COLD declares that the function is rarely executed. */
+/* Applies to: functions. */
/* Avoid __attribute__ ((cold)) on MinGW; see thread starting at
<https://lists.gnu.org/r/emacs-devel/2019-04/msg01152.html>.
Also, Oracle Studio 12.6 requires 'cold' not '__cold__'. */
@@ -133,13 +163,46 @@ AC_DEFUN([gl_COMMON_BODY], [
# define _GL_ATTRIBUTE_COLD
#endif
+/* _GL_ATTRIBUTE_CONST declares that it is OK for a compiler to omit duplicate
+ calls to the function with the same arguments.
+ This attribute is safe for a function that neither depends on nor affects
+ observable state, and always returns exactly once - e.g., does not loop
+ forever, and does not call longjmp.
+ (This attribute is stricter than _GL_ATTRIBUTE_PURE.) */
+/* Applies to: functions. */
#if _GL_HAS_ATTRIBUTE (const)
# define _GL_ATTRIBUTE_CONST __attribute__ ((__const__))
#else
# define _GL_ATTRIBUTE_CONST
#endif
-#if 201710L < __STDC_VERSION__
+/* _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. */
+#if _GL_GNUC_PREREQ (11, 0)
+# define _GL_ATTRIBUTE_DEALLOC(f, i) __attribute__ ((__malloc__ (f, i)))
+#else
+# define _GL_ATTRIBUTE_DEALLOC(f, i)
+#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
+# define _GL_ATTRIBUTE_DEALLOC_FREE _GL_ATTRIBUTE_DEALLOC (free, 1)
+#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. */
+#if _GL_HAS_C_ATTRIBUTE (deprecated)
# define _GL_ATTRIBUTE_DEPRECATED [[__deprecated__]]
#elif _GL_HAS_ATTRIBUTE (deprecated)
# define _GL_ATTRIBUTE_DEPRECATED __attribute__ ((__deprecated__))
@@ -147,6 +210,11 @@ AC_DEFUN([gl_COMMON_BODY], [
# define _GL_ATTRIBUTE_DEPRECATED
#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 _GL_HAS_ATTRIBUTE (error)
# define _GL_ATTRIBUTE_ERROR(msg) __attribute__ ((__error__ (msg)))
# define _GL_ATTRIBUTE_WARNING(msg) __attribute__ ((__warning__ (msg)))
@@ -158,14 +226,21 @@ AC_DEFUN([gl_COMMON_BODY], [
# define _GL_ATTRIBUTE_WARNING(msg)
#endif
+/* _GL_ATTRIBUTE_EXTERNALLY_VISIBLE declares that the entity should remain
+ visible to debuggers etc., even with '-fwhole-program'. */
+/* Applies to: functions, variables. */
#if _GL_HAS_ATTRIBUTE (externally_visible)
# define _GL_ATTRIBUTE_EXTERNALLY_VISIBLE __attribute__ ((externally_visible))
#else
# define _GL_ATTRIBUTE_EXTERNALLY_VISIBLE
#endif
-/* FALLTHROUGH is special, because it always expands to something. */
-#if 201710L < __STDC_VERSION__
+/* _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. */
+#if _GL_HAS_C_ATTRIBUTE (fallthrough)
# define _GL_ATTRIBUTE_FALLTHROUGH [[__fallthrough__]]
#elif _GL_HAS_ATTRIBUTE (fallthrough)
# define _GL_ATTRIBUTE_FALLTHROUGH __attribute__ ((__fallthrough__))
@@ -173,18 +248,47 @@ AC_DEFUN([gl_COMMON_BODY], [
# define _GL_ATTRIBUTE_FALLTHROUGH ((void) 0)
#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. */
#if _GL_HAS_ATTRIBUTE (format)
# define _GL_ATTRIBUTE_FORMAT(spec) __attribute__ ((__format__ spec))
#else
# define _GL_ATTRIBUTE_FORMAT(spec)
#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. */
#if _GL_HAS_ATTRIBUTE (leaf)
# define _GL_ATTRIBUTE_LEAF __attribute__ ((__leaf__))
#else
# define _GL_ATTRIBUTE_LEAF
#endif
+/* _GL_ATTRIBUTE_MALLOC declares that the function returns a pointer to freshly
+ allocated memory. */
+/* Applies to: functions. */
+#if _GL_HAS_ATTRIBUTE (malloc)
+# define _GL_ATTRIBUTE_MALLOC __attribute__ ((__malloc__))
+#else
+# define _GL_ATTRIBUTE_MALLOC
+#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. */
#if _GL_HAS_ATTRIBUTE (may_alias) && !defined __SUNPRO_C
# define _GL_ATTRIBUTE_MAY_ALIAS __attribute__ ((__may_alias__))
@@ -192,24 +296,33 @@ AC_DEFUN([gl_COMMON_BODY], [
# define _GL_ATTRIBUTE_MAY_ALIAS
#endif
-#if 201710L < __STDC_VERSION__
+/* _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 C2x, this is spelled [[__maybe_unused__]].
+ GCC's syntax is __attribute__ ((__unused__)).
+ clang supports both syntaxes. */
+#if _GL_HAS_C_ATTRIBUTE (maybe_unused)
# define _GL_ATTRIBUTE_MAYBE_UNUSED [[__maybe_unused__]]
-#elif _GL_HAS_ATTRIBUTE (unused)
-# define _GL_ATTRIBUTE_MAYBE_UNUSED __attribute__ ((__unused__))
#else
-# define _GL_ATTRIBUTE_MAYBE_UNUSED
+# define _GL_ATTRIBUTE_MAYBE_UNUSED _GL_ATTRIBUTE_UNUSED
#endif
-/* Earlier spellings of this macro. */
+/* Alternative spelling of this macro, for convenience. */
#define _GL_UNUSED _GL_ATTRIBUTE_MAYBE_UNUSED
+/* Earlier spellings of this macro. */
#define _UNUSED_PARAMETER_ _GL_ATTRIBUTE_MAYBE_UNUSED
-#if _GL_HAS_ATTRIBUTE (malloc)
-# define _GL_ATTRIBUTE_MALLOC __attribute__ ((__malloc__))
-#else
-# define _GL_ATTRIBUTE_MALLOC
-#endif
-
-#if 201710L < __STDC_VERSION__
+/* _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. */
+#if _GL_HAS_C_ATTRIBUTE (nodiscard)
# define _GL_ATTRIBUTE_NODISCARD [[__nodiscard__]]
#elif _GL_HAS_ATTRIBUTE (warn_unused_result)
# define _GL_ATTRIBUTE_NODISCARD __attribute__ ((__warn_unused_result__))
@@ -217,18 +330,30 @@ AC_DEFUN([gl_COMMON_BODY], [
# define _GL_ATTRIBUTE_NODISCARD
#endif
+/* _GL_ATTRIBUTE_NOINLINE tells that the compiler should not inline the
+ function. */
+/* Applies to: functions. */
#if _GL_HAS_ATTRIBUTE (noinline)
# define _GL_ATTRIBUTE_NOINLINE __attribute__ ((__noinline__))
#else
# define _GL_ATTRIBUTE_NOINLINE
#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. */
#if _GL_HAS_ATTRIBUTE (nonnull)
# define _GL_ATTRIBUTE_NONNULL(args) __attribute__ ((__nonnull__ args))
#else
# define _GL_ATTRIBUTE_NONNULL(args)
#endif
+/* _GL_ATTRIBUTE_NONSTRING declares that the contents of a character array is
+ not meant to be NUL-terminated. */
+/* Applies to: struct/union members and variables that are arrays of element
+ type '[[un]signed] char'. */
#if _GL_HAS_ATTRIBUTE (nonstring)
# define _GL_ATTRIBUTE_NONSTRING __attribute__ ((__nonstring__))
#else
@@ -237,41 +362,77 @@ AC_DEFUN([gl_COMMON_BODY], [
/* There is no _GL_ATTRIBUTE_NORETURN; use _Noreturn instead. */
+/* _GL_ATTRIBUTE_NOTHROW declares that the function does not throw exceptions.
+ */
+/* Applies to: functions. */
#if _GL_HAS_ATTRIBUTE (nothrow) && !defined __cplusplus
# define _GL_ATTRIBUTE_NOTHROW __attribute__ ((__nothrow__))
#else
# define _GL_ATTRIBUTE_NOTHROW
#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. */
#if _GL_HAS_ATTRIBUTE (packed)
# define _GL_ATTRIBUTE_PACKED __attribute__ ((__packed__))
#else
# define _GL_ATTRIBUTE_PACKED
#endif
+/* _GL_ATTRIBUTE_PURE declares that It is OK for a compiler to omit duplicate
+ calls to the function with the same arguments if observable state is not
+ changed between calls.
+ This attribute is safe for a function that does not affect
+ observable state, and always returns exactly once.
+ (This attribute is looser than _GL_ATTRIBUTE_CONST.) */
+/* Applies to: functions. */
#if _GL_HAS_ATTRIBUTE (pure)
# define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
#else
# define _GL_ATTRIBUTE_PURE
#endif
+/* _GL_ATTRIBUTE_RETURNS_NONNULL declares that the function's return value is
+ a non-NULL pointer. */
+/* Applies to: functions. */
#if _GL_HAS_ATTRIBUTE (returns_nonnull)
# define _GL_ATTRIBUTE_RETURNS_NONNULL __attribute__ ((__returns_nonnull__))
#else
# define _GL_ATTRIBUTE_RETURNS_NONNULL
#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. */
#if _GL_HAS_ATTRIBUTE (sentinel)
# define _GL_ATTRIBUTE_SENTINEL(pos) __attribute__ ((__sentinel__ pos))
#else
# define _GL_ATTRIBUTE_SENTINEL(pos)
#endif
+/* A helper macro. Don't use it directly. */
+#if _GL_HAS_ATTRIBUTE (unused)
+# define _GL_ATTRIBUTE_UNUSED __attribute__ ((__unused__))
+#else
+# define _GL_ATTRIBUTE_UNUSED
+#endif
+
]dnl There is no _GL_ATTRIBUTE_VISIBILITY; see m4/visibility.m4 instead.
[
-/* To support C++ as well as C, use _GL_UNUSED_LABEL with trailing ';'. */
-#if !defined __cplusplus || _GL_GNUC_PREREQ (4, 5)
-# define _GL_UNUSED_LABEL _GL_ATTRIBUTE_MAYBE_UNUSED
+/* _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. */
+#if !(defined __cplusplus && !_GL_GNUC_PREREQ (4, 5)) || defined __clang__
+# define _GL_UNUSED_LABEL _GL_ATTRIBUTE_UNUSED
#else
# define _GL_UNUSED_LABEL
#endif
@@ -354,6 +515,16 @@ AC_DEFUN([gl_COMMON_BODY], [
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
@@ -366,9 +537,9 @@ m4_define([gl_MODULE_INDICATOR_CONDITION], [1])
AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE],
[
gl_MODULE_INDICATOR_SET_VARIABLE_AUX(
- [GNULIB_[]m4_translit([[$1]],
- [abcdefghijklmnopqrstuvwxyz./-],
- [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])],
+ [GL_MODULE_INDICATOR_PREFIX[]_GNULIB_[]m4_translit([[$1]],
+ [abcdefghijklmnopqrstuvwxyz./-],
+ [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])],
[gl_MODULE_INDICATOR_CONDITION])
])
@@ -653,6 +824,186 @@ AC_DEFUN([gl_CACHE_VAL_SILENT],
])
])
+# 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-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 || (__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 || (__clang_major__ + (__clang_minor__ >= 9) > 3)
+ -Wno-float-conversion
+ #endif
+ #if __GNUC__ >= 7 || (__clang_major__ + (__clang_minor__ >= 9) > 3)
+ -Wimplicit-fallthrough
+ #endif
+ #if __GNUC__ + (__GNUC_MINOR__ >= 8) > 4 || (__clang_major__ + (__clang_minor__ >= 9) > 3)
+ -Wno-pedantic
+ #endif
+ #if __GNUC__ + (__GNUC_MINOR__ >= 3) > 4 || (__clang_major__ + (__clang_minor__ >= 9) > 3)
+ -Wno-sign-conversion
+ -Wno-type-limits
+ #endif
+ #if __GNUC__ + (__GNUC_MINOR__ >= 5) > 4
+ -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 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