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-rw-r--r--m4/gnulib-common.m41398
1 files changed, 1398 insertions, 0 deletions
diff --git a/m4/gnulib-common.m4 b/m4/gnulib-common.m4
new file mode 100644
index 0000000..c84a2af
--- /dev/null
+++ b/m4/gnulib-common.m4
@@ -0,0 +1,1398 @@
+# gnulib-common.m4 serial 82
+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,
+dnl with or without modifications, as long as this notice is preserved.
+
+AC_PREREQ([2.62])
+
+# gl_COMMON
+# is expanded unconditionally through gnulib-tool magic.
+AC_DEFUN([gl_COMMON], [
+ dnl Use AC_REQUIRE here, so that the code is expanded once only.
+ AC_REQUIRE([gl_00GNULIB])
+ AC_REQUIRE([gl_COMMON_BODY])
+ AC_REQUIRE([gl_ZZGNULIB])
+])
+AC_DEFUN([gl_COMMON_BODY], [
+ AH_VERBATIM([_GL_GNUC_PREREQ],
+[/* True if the compiler says it groks GNU C version MAJOR.MINOR. */
+#if defined __GNUC__ && defined __GNUC_MINOR__
+# define _GL_GNUC_PREREQ(major, minor) \
+ ((major) < __GNUC__ + ((minor) <= __GNUC_MINOR__))
+#else
+# define _GL_GNUC_PREREQ(major, minor) 0
+#endif
+])
+ AH_VERBATIM([_Noreturn],
+[/* The _Noreturn keyword of C11. */
+#ifndef _Noreturn
+# if (defined __cplusplus \
+ && ((201103 <= __cplusplus && !(__GNUC__ == 4 && __GNUC_MINOR__ == 7)) \
+ || (defined _MSC_VER && 1900 <= _MSC_VER)) \
+ && 0)
+ /* [[noreturn]] is not practically usable, because with it the syntax
+ extern _Noreturn void func (...);
+ would not be valid; such a declaration would only be valid with 'extern'
+ and '_Noreturn' swapped, or without the 'extern' keyword. However, some
+ AIX system header files and several gnulib header files use precisely
+ this syntax with 'extern'. */
+# define _Noreturn [[noreturn]]
+# elif (defined __clang__ && __clang_major__ < 16 \
+ && defined _GL_WORK_AROUND_LLVM_BUG_59792)
+ /* Compile with -D_GL_WORK_AROUND_LLVM_BUG_59792 to work around
+ that rare LLVM bug, though you may get many false-alarm warnings. */
+# define _Noreturn
+# elif ((!defined __cplusplus || defined __clang__) \
+ && (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__))
+# elif 1200 <= (defined _MSC_VER ? _MSC_VER : 0)
+# define _Noreturn __declspec (noreturn)
+# else
+# define _Noreturn
+# endif
+#endif
+])
+ AH_VERBATIM([isoc99_inline],
+[/* Work around a bug in Apple GCC 4.0.1 build 5465: In C99 mode, it supports
+ the ISO C 99 semantics of 'extern inline' (unlike the GNU C semantics of
+ earlier versions), but does not display it by setting __GNUC_STDC_INLINE__.
+ __APPLE__ && __MACH__ test for Mac OS X.
+ __APPLE_CC__ tests for the Apple compiler and its version.
+ __STDC_VERSION__ tests for the C99 mode. */
+#if defined __APPLE__ && defined __MACH__ && __APPLE_CC__ >= 5465 && !defined __cplusplus && __STDC_VERSION__ >= 199901L && !defined __GNUC_STDC_INLINE__
+# define __GNUC_STDC_INLINE__ 1
+#endif])
+ AH_VERBATIM([attribute],
+[/* Attributes. */
+#if (defined __has_attribute \
+ && (!defined __clang_minor__ \
+ || (defined __apple_build_version__ \
+ ? 6000000 <= __apple_build_version__ \
+ : 5 <= __clang_major__)))
+# define _GL_HAS_ATTRIBUTE(attr) __has_attribute (__##attr##__)
+#else
+# define _GL_HAS_ATTRIBUTE(attr) _GL_ATTR_##attr
+# define _GL_ATTR_alloc_size _GL_GNUC_PREREQ (4, 3)
+# define _GL_ATTR_always_inline _GL_GNUC_PREREQ (3, 2)
+# define _GL_ATTR_artificial _GL_GNUC_PREREQ (4, 3)
+# define _GL_ATTR_cold _GL_GNUC_PREREQ (4, 3)
+# define _GL_ATTR_const _GL_GNUC_PREREQ (2, 95)
+# define _GL_ATTR_deprecated _GL_GNUC_PREREQ (3, 1)
+# define _GL_ATTR_diagnose_if 0
+# define _GL_ATTR_error _GL_GNUC_PREREQ (4, 3)
+# define _GL_ATTR_externally_visible _GL_GNUC_PREREQ (4, 1)
+# 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_noinline _GL_GNUC_PREREQ (3, 1)
+# define _GL_ATTR_nonnull _GL_GNUC_PREREQ (3, 3)
+# define _GL_ATTR_nonstring _GL_GNUC_PREREQ (8, 0)
+# define _GL_ATTR_nothrow _GL_GNUC_PREREQ (3, 3)
+# define _GL_ATTR_packed _GL_GNUC_PREREQ (2, 7)
+# define _GL_ATTR_pure _GL_GNUC_PREREQ (2, 96)
+# define _GL_ATTR_returns_nonnull _GL_GNUC_PREREQ (4, 9)
+# define _GL_ATTR_sentinel _GL_GNUC_PREREQ (4, 0)
+# define _GL_ATTR_unused _GL_GNUC_PREREQ (2, 7)
+# define _GL_ATTR_warn_unused_result _GL_GNUC_PREREQ (3, 4)
+#endif
+
+/* Disable GCC -Wpedantic if using __has_c_attribute and this is not C23+. */
+#if (defined __has_c_attribute && _GL_GNUC_PREREQ (4, 6) \
+ && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) <= 201710)
+# pragma GCC diagnostic ignored "-Wpedantic"
+#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. */
+#ifndef _GL_ATTRIBUTE_ALLOC_SIZE
+# if _GL_HAS_ATTRIBUTE (alloc_size)
+# define _GL_ATTRIBUTE_ALLOC_SIZE(args) __attribute__ ((__alloc_size__ args))
+# else
+# define _GL_ATTRIBUTE_ALLOC_SIZE(args)
+# endif
+#endif
+
+/* _GL_ATTRIBUTE_ALWAYS_INLINE tells that the compiler should always inline the
+ function and report an error if it cannot do so. */
+/* Applies to: function. */
+#ifndef _GL_ATTRIBUTE_ALWAYS_INLINE
+# if _GL_HAS_ATTRIBUTE (always_inline)
+# define _GL_ATTRIBUTE_ALWAYS_INLINE __attribute__ ((__always_inline__))
+# else
+# define _GL_ATTRIBUTE_ALWAYS_INLINE
+# endif
+#endif
+
+/* _GL_ATTRIBUTE_ARTIFICIAL declares that the function is not important to show
+ in stack traces when debugging. The compiler should omit the function from
+ stack traces. */
+/* Applies to: function. */
+#ifndef _GL_ATTRIBUTE_ARTIFICIAL
+# if _GL_HAS_ATTRIBUTE (artificial)
+# define _GL_ATTRIBUTE_ARTIFICIAL __attribute__ ((__artificial__))
+# else
+# define _GL_ATTRIBUTE_ARTIFICIAL
+# endif
+#endif
+
+/* _GL_ATTRIBUTE_COLD declares that the function is rarely executed. */
+/* 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__'. */
+#ifndef _GL_ATTRIBUTE_COLD
+# if _GL_HAS_ATTRIBUTE (cold) && !defined __MINGW32__
+# ifndef __SUNPRO_C
+# define _GL_ATTRIBUTE_COLD __attribute__ ((__cold__))
+# else
+# define _GL_ATTRIBUTE_COLD __attribute__ ((cold))
+# endif
+# else
+# define _GL_ATTRIBUTE_COLD
+# endif
+#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. */
+#ifndef _GL_ATTRIBUTE_CONST
+# if _GL_HAS_ATTRIBUTE (const)
+# define _GL_ATTRIBUTE_CONST __attribute__ ((__const__))
+# else
+# define _GL_ATTRIBUTE_CONST
+# endif
+#endif
+
+/* _GL_ATTRIBUTE_DEALLOC (F, I) declares that the function returns pointers
+ 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
+# ifdef __has_c_attribute
+# if __has_c_attribute (__deprecated__)
+# define _GL_ATTRIBUTE_DEPRECATED [[__deprecated__]]
+# endif
+# endif
+# if !defined _GL_ATTRIBUTE_DEPRECATED && _GL_HAS_ATTRIBUTE (deprecated)
+# define _GL_ATTRIBUTE_DEPRECATED __attribute__ ((__deprecated__))
+# endif
+# ifndef _GL_ATTRIBUTE_DEPRECATED
+# define _GL_ATTRIBUTE_DEPRECATED
+# endif
+#endif
+
+/* _GL_ATTRIBUTE_ERROR(msg) requests an error if a function is called and
+ 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
+# ifdef __has_c_attribute
+# if __has_c_attribute (__fallthrough__)
+# define _GL_ATTRIBUTE_FALLTHROUGH [[__fallthrough__]]
+# endif
+# endif
+# if !defined _GL_ATTRIBUTE_FALLTHROUGH && _GL_HAS_ATTRIBUTE (fallthrough)
+# define _GL_ATTRIBUTE_FALLTHROUGH __attribute__ ((__fallthrough__))
+# endif
+# ifndef _GL_ATTRIBUTE_FALLTHROUGH
+# define _GL_ATTRIBUTE_FALLTHROUGH ((void) 0)
+# endif
+#endif
+
+/* _GL_ATTRIBUTE_FORMAT ((ARCHETYPE, STRING-INDEX, FIRST-TO-CHECK))
+ 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
+# 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
+# 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
+# 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__]]
+# 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. */
+#ifndef _GL_ATTRIBUTE_NOTHROW
+# if _GL_HAS_ATTRIBUTE (nothrow) && !defined __cplusplus
+# define _GL_ATTRIBUTE_NOTHROW __attribute__ ((__nothrow__))
+# else
+# define _GL_ATTRIBUTE_NOTHROW
+# endif
+#endif
+
+/* _GL_ATTRIBUTE_PACKED declares:
+ 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
+# if _GL_HAS_ATTRIBUTE (packed)
+# define _GL_ATTRIBUTE_PACKED __attribute__ ((__packed__))
+# else
+# define _GL_ATTRIBUTE_PACKED
+# endif
+#endif
+
+/* _GL_ATTRIBUTE_PURE declares that It is OK for a compiler to omit duplicate
+ 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. */
+#ifndef _GL_ATTRIBUTE_PURE
+# if _GL_HAS_ATTRIBUTE (pure)
+# define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
+# else
+# define _GL_ATTRIBUTE_PURE
+# endif
+#endif
+
+/* _GL_ATTRIBUTE_RETURNS_NONNULL declares that the function's return value is
+ a non-NULL pointer. */
+/* Applies to: functions. */
+#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
+
+/* 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([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-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 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 $gl_cv_compiler_clang = yes; then
+ dnl Test whether the compiler supports the option
+ dnl '-Werror=unguarded-availability-new'.
+ save_ac_compile="$ac_compile"
+ ac_compile="$ac_compile -Werror=unguarded-availability-new"
+ AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]],[[]])],
+ [gl_cv_compiler_check_future_option='-Werror=unguarded-availability-new'],
+ [gl_cv_compiler_check_future_option=none])
+ ac_compile="$save_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.
+ save_ac_compile="$ac_compile"
+ ac_compile="$ac_compile $gl_cv_compiler_check_future_option"
+ save_ac_compile_for_check_decl="$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], , , [$2])
+ ac_compile="$save_ac_compile"
+ ac_compile_for_check_decl="$save_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
+#define execlp _execlp
+#define execv _execv
+#define execve _execve
+#define execvp _execvp
+#define execvpe _execvpe
+#define fcloseall _fcloseall
+#define fcvt _fcvt
+#define fdopen _fdopen
+#define fileno _fileno
+#define gcvt _gcvt
+#define getcwd _getcwd
+#define getpid _getpid
+#define getw _getw
+#define isatty _isatty
+#define j0 _j0
+#define j1 _j1
+#define jn _jn
+#define lfind _lfind
+#define lsearch _lsearch
+#define lseek _lseek
+#define memccpy _memccpy
+#define mkdir _mkdir
+#define mktemp _mktemp
+#define open _open
+#define putenv _putenv
+#define putw _putw
+#define read _read
+#define rmdir _rmdir
+#define strdup _strdup
+#define swab _swab
+#define tempnam _tempnam
+#define tzset _tzset
+#define umask _umask
+#define unlink _unlink
+#define utime _utime
+#define wcsdup _wcsdup
+#define write _write
+#define y0 _y0
+#define y1 _y1
+#define yn _yn
+#endif
+'
+])