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Diffstat (limited to 'm4/gnulib-common.m4')
| -rw-r--r-- | m4/gnulib-common.m4 | 463 |
1 files changed, 463 insertions, 0 deletions
diff --git a/m4/gnulib-common.m4 b/m4/gnulib-common.m4 new file mode 100644 index 0000000..b4795c1 --- /dev/null +++ b/m4/gnulib-common.m4 @@ -0,0 +1,463 @@ +# gnulib-common.m4 serial 48 +dnl Copyright (C) 2007-2020 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([_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 __cplusplus || defined __clang__) \ + && (201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) \ + || 4 < __GNUC__ + (7 <= __GNUC_MINOR__) \ + || (defined __apple_build_version__ \ + ? 6000000 <= __apple_build_version__ \ + : 3 < __clang_major__ + (5 <= __clang_minor__)))) + /* _Noreturn works as-is. */ +# elif 2 < __GNUC__ + (8 <= __GNUC_MINOR__) || 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([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__)) +#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 +#else +# define _GL_UNUSED_LABEL +#endif + +/* The __pure__ attribute was added in gcc 2.96. */ +#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96) +# define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__)) +#else +# define _GL_ATTRIBUTE_PURE /* empty */ +#endif + +/* The __const__ attribute was added in gcc 2.95. */ +#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 95) +# define _GL_ATTRIBUTE_CONST __attribute__ ((__const__)) +#else +# define _GL_ATTRIBUTE_CONST /* empty */ +#endif + +/* The __malloc__ attribute was added in gcc 3. */ +#if 3 <= __GNUC__ +# define _GL_ATTRIBUTE_MALLOC __attribute__ ((__malloc__)) +#else +# define _GL_ATTRIBUTE_MALLOC /* empty */ +#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 +]) + 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_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( + [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]) +]) + +# 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 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])]) +]) + +# 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-2.69 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. +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 + 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 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 +]) + +# 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], +[ + saved_as_echo_n="$as_echo_n" + as_echo_n=':' + AC_CACHE_VAL([$1], [$2]) + as_echo_n="$saved_as_echo_n" +]) + +# 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])]) |