diff options
Diffstat (limited to 'gnulib-m4/gnulib-common.m4')
| -rw-r--r-- | gnulib-m4/gnulib-common.m4 | 852 |
1 files changed, 679 insertions, 173 deletions
diff --git a/gnulib-m4/gnulib-common.m4 b/gnulib-m4/gnulib-common.m4 index 736e4210..87a9a751 100644 --- a/gnulib-m4/gnulib-common.m4 +++ b/gnulib-m4/gnulib-common.m4 @@ -1,25 +1,54 @@ -# gnulib-common.m4 serial 39 -dnl Copyright (C) 2007-2018 Free Software Foundation, Inc. +# gnulib-common.m4 serial 69 +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. +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. */ -#if ! (defined _Noreturn \ - || (defined __STDC_VERSION__ && 201112 <= __STDC_VERSION__)) -# if (3 <= __GNUC__ || (__GNUC__ == 2 && 8 <= __GNUC_MINOR__) \ - || 0x5110 <= __SUNPRO_C) +#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 __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 defined _MSC_VER && 1200 <= _MSC_VER +# elif 1200 <= (defined _MSC_VER ? _MSC_VER : 0) # define _Noreturn __declspec (noreturn) # else # define _Noreturn @@ -36,50 +65,437 @@ AC_DEFUN([gl_COMMON_BODY], [ #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([unused_parameter], -[/* Define as a marker that can be attached to declarations that might not - be used. This helps to reduce warnings, such as from - GCC -Wunused-parameter. */ -#if __GNUC__ >= 3 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 7) -# define _GL_UNUSED __attribute__ ((__unused__)) + AH_VERBATIM([attribute], +[/* Attributes. */ +#if (defined __has_attribute \ + && (!defined __clang_minor__ \ + || 3 < __clang_major__ + (5 <= __clang_minor__))) +# define _GL_HAS_ATTRIBUTE(attr) __has_attribute (__##attr##__) #else -# define _GL_UNUSED -#endif -/* The name _UNUSED_PARAMETER_ is an earlier spelling, although the name - is a misnomer outside of parameter lists. */ -#define _UNUSED_PARAMETER_ _GL_UNUSED - -/* gcc supports the "unused" attribute on possibly unused labels, and - g++ has since version 4.5. Note to support C++ as well as C, - _GL_UNUSED_LABEL should be used with a trailing ; */ -#if !defined __cplusplus || __GNUC__ > 4 \ - || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5) -# define _GL_UNUSED_LABEL _GL_UNUSED +# 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 + +#ifdef __has_c_attribute +# define _GL_HAS_C_ATTRIBUTE(attr) __has_c_attribute (__##attr##__) #else -# define _GL_UNUSED_LABEL +# define _GL_HAS_C_ATTRIBUTE(attr) 0 #endif -/* The __pure__ attribute was added in gcc 2.96. */ -#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96) -# define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__)) +]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__'. */ +#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_PURE /* empty */ +# define _GL_ATTRIBUTE_COLD #endif -/* The __const__ attribute was added in gcc 2.95. */ -#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 95) +/* _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 /* empty */ +# define _GL_ATTRIBUTE_CONST #endif -/* The __malloc__ attribute was added in gcc 3. */ -#if 3 <= __GNUC__ +/* _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 +#define _GL_ATTRIBUTE_DEALLOC_FREE _GL_ATTRIBUTE_DEALLOC (free, 1) + +/* _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__)) +#else +# 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))) +#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 + +/* _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 + +/* _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__)) +#else +# 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 /* empty */ +# 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__)) +#else +# define _GL_ATTRIBUTE_MAY_ALIAS +#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 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__]] +#else +# define _GL_ATTRIBUTE_MAYBE_UNUSED _GL_ATTRIBUTE_UNUSED +#endif +/* 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 + +/* _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__)) +#else +# 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 +# define _GL_ATTRIBUTE_NONSTRING +#endif + +/* There is no _GL_ATTRIBUTE_NORETURN; use _Noreturn instead. */ + +/* _GL_ATTRIBUTE_NOTHROW declares that the function does not throw exceptions. + */ +/* Applies to: functions. */ +#if _GL_HAS_ATTRIBUTE (nothrow) && !defined __cplusplus +# define _GL_ATTRIBUTE_NOTHROW __attribute__ ((__nothrow__)) +#else +# define _GL_ATTRIBUTE_NOTHROW +#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. +[ +/* _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 ]) + 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 @@ -88,6 +504,16 @@ 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 @@ -100,9 +526,9 @@ 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]) ]) @@ -214,42 +640,20 @@ AC_DEFUN([gl_FEATURES_H], AC_SUBST([HAVE_FEATURES_H]) ]) -# m4_foreach_w -# is a backport of autoconf-2.59c's m4_foreach_w. -# Remove this macro when we can assume autoconf >= 2.60. -m4_ifndef([m4_foreach_w], - [m4_define([m4_foreach_w], - [m4_foreach([$1], m4_split(m4_normalize([$2]), [ ]), [$3])])]) - -# AS_VAR_IF(VAR, VALUE, [IF-MATCH], [IF-NOT-MATCH]) -# ---------------------------------------------------- -# Backport of autoconf-2.63b's macro. -# Remove this macro when we can assume autoconf >= 2.64. -m4_ifndef([AS_VAR_IF], -[m4_define([AS_VAR_IF], -[AS_IF([test x"AS_VAR_GET([$1])" = x""$2], [$3], [$4])])]) - # gl_PROG_CC_C99 # Modifies the value of the shell variable CC in an attempt to make $CC # understand ISO C99 source code. -# This is like AC_PROG_CC_C99, except that -# - AC_PROG_CC_C99 did not exist in Autoconf versions < 2.60, -# - AC_PROG_CC_C99 does not mix well with AC_PROG_CC_STDC -# <https://lists.gnu.org/r/bug-gnulib/2011-09/msg00367.html>, -# but many more packages use AC_PROG_CC_STDC than AC_PROG_CC_C99 -# <https://lists.gnu.org/r/bug-gnulib/2011-09/msg00441.html>. -# Remaining problems: -# - When AC_PROG_CC_STDC is invoked twice, it adds the C99 enabling options -# to CC twice -# <https://lists.gnu.org/r/bug-gnulib/2011-09/msg00431.html>. -# - AC_PROG_CC_STDC is likely to change now that C11 is an ISO standard. AC_DEFUN([gl_PROG_CC_C99], [ - dnl Change that version number to the minimum Autoconf version that supports - dnl mixing AC_PROG_CC_C99 calls with AC_PROG_CC_STDC calls. - m4_version_prereq([9.0], - [AC_REQUIRE([AC_PROG_CC_C99])], - [AC_REQUIRE([AC_PROG_CC_STDC])]) + 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 @@ -322,48 +726,29 @@ Amsterdam AC_SUBST([RANLIB]) ]) -# AC_PROG_MKDIR_P -# is a backport of autoconf-2.60's AC_PROG_MKDIR_P, with a fix -# for interoperability with automake-1.9.6 from autoconf-2.62. -# Remove this macro when we can assume autoconf >= 2.62 or -# autoconf >= 2.60 && automake >= 1.10. -# AC_AUTOCONF_VERSION was introduced in 2.62, so use that as the witness. -m4_ifndef([AC_AUTOCONF_VERSION],[ -m4_ifdef([AC_PROG_MKDIR_P], [ - dnl For automake-1.9.6 && autoconf < 2.62: Ensure MKDIR_P is AC_SUBSTed. - m4_define([AC_PROG_MKDIR_P], - m4_defn([AC_PROG_MKDIR_P])[ - AC_SUBST([MKDIR_P])])], [ - dnl For autoconf < 2.60: Backport of AC_PROG_MKDIR_P. - AC_DEFUN_ONCE([AC_PROG_MKDIR_P], - [AC_REQUIRE([AM_PROG_MKDIR_P])dnl defined by automake - MKDIR_P='$(mkdir_p)' - AC_SUBST([MKDIR_P])])]) -]) - # AC_C_RESTRICT -# This definition is copied from post-2.69 Autoconf and overrides the -# AC_C_RESTRICT macro from autoconf 2.60..2.69. It can be removed -# once autoconf >= 2.70 can be assumed. It's painful to check version -# numbers, and in practice this macro is more up-to-date than Autoconf -# is, so override Autoconf unconditionally. +# 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 - # The order here caters to the fact that C++ does not require restrict. - for ac_kw in __restrict __restrict__ _Restrict restrict; do + # 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); - ]])], + [[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 @@ -371,14 +756,15 @@ AC_DEFUN([AC_C_RESTRICT], 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 directly. */ + supported only directly. */ #undef restrict -/* Work around a bug in Sun C++: it does not support _Restrict or - __restrict__, even though the corresponding Sun C compiler ends up with - "#define restrict _Restrict" or "#define restrict __restrict__" in the - previous line. Perhaps some future version of Sun C++ will work with - restrict; if so, hopefully it defines __RESTRICT like Sun C does. */ -#if defined __SUNPRO_CC && !defined __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]) @@ -388,6 +774,7 @@ AC_DEFUN([AC_C_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. @@ -398,6 +785,22 @@ 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 + $1 + exec AS_MESSAGE_FD>&GL_TMP_FD GL_TMP_FD>&- +]) + # gl_CACHE_VAL_SILENT(cache-id, command-to-set-it) # is like AC_CACHE_VAL(cache-id, command-to-set-it), except that it does not # output a spurious "(cached)" mark in the midst of other configure output. @@ -405,70 +808,173 @@ AC_DEFUN([gl_BIGENDIAN], # by an AC_MSG_CHECKING/AC_MSG_RESULT pair. AC_DEFUN([gl_CACHE_VAL_SILENT], [ - saved_as_echo_n="$as_echo_n" - as_echo_n=':' - AC_CACHE_VAL([$1], [$2]) - as_echo_n="$saved_as_echo_n" + gl_SILENT([ + AC_CACHE_VAL([$1], [$2]) + ]) ]) -# AS_VAR_COPY was added in autoconf 2.63b -m4_define_default([AS_VAR_COPY], -[AS_LITERAL_IF([$1[]$2], [$1=$$2], [eval $1=\$$2])]) - -# AC_PROG_SED was added in autoconf 2.59b -m4_ifndef([AC_PROG_SED], -[AC_DEFUN([AC_PROG_SED], -[AC_CACHE_CHECK([for a sed that does not truncate output], ac_cv_path_SED, - [dnl ac_script should not contain more than 99 commands (for HP-UX sed), - dnl but more than about 7000 bytes, to catch a limit in Solaris 8 /usr/ucb/sed. - ac_script=s/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb/ - for ac_i in 1 2 3 4 5 6 7; do - ac_script="$ac_script$as_nl$ac_script" - done - echo "$ac_script" 2>/dev/null | sed 99q >conftest.sed - AS_UNSET([ac_script]) - if test -z "$SED"; then - ac_path_SED_found=false - _AS_PATH_WALK([], [ - for ac_prog in sed gsed; do - for ac_exec_ext in '' $ac_executable_extensions; do - ac_path_SED="$as_dir/$ac_prog$ac_exec_ext" - AS_EXECUTABLE_P(["$ac_path_SED"]) || continue - case `"$ac_path_SED" --version 2>&1` in - *GNU*) ac_cv_path_SED=$ac_path_SED ac_path_SED_found=:;; - *) - ac_count=0 - _AS_ECHO_N([0123456789]) >conftest.in - while : - do - cat conftest.in conftest.in >conftest.tmp - mv conftest.tmp conftest.in - cp conftest.in conftest.nl - echo >> conftest.nl - "$ac_path_SED" -f conftest.sed <conftest.nl >conftest.out 2>/dev/null || break - diff conftest.out conftest.nl >/dev/null 2>&1 || break - ac_count=`expr $ac_count + 1` - if test $ac_count -gt ${ac_path_SED_max-0}; then - # Best so far, but keep looking for better - ac_cv_path_SED=$ac_path_SED - ac_path_SED_max=$ac_count - fi - test $ac_count -gt 10 && break - done - rm -f conftest.in conftest.tmp conftest.nl conftest.out;; - esac - $ac_path_SED_found && break 3 - done - done]) - if test -z "$ac_cv_path_SED"; then - AC_ERROR([no acceptable sed could be found in \$PATH]) - 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 $? = 0 && test `wc -l < conftest1.err` = `wc -l < conftest2.err`; then + gl_cv_cc_wallow='-Wno-error' else - ac_cv_path_SED=$SED + gl_cv_cc_wallow=none fi + rm -f conftest* ]) - SED="$ac_cv_path_SED" - AC_SUBST([SED])dnl - rm -f conftest.sed + case "$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]) +]) + +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}$1" + fi + ;; + *) echo "*** gl_generate_var is not set correctly" 1>&2; exit 1 ;; + esac + AC_SUBST(gl_header_name) + AM_CONDITIONAL(gl_generate_cond, [$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 +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 +' ]) |