diff options
Diffstat (limited to 'm4/gnulib-common.m4')
| -rw-r--r-- | m4/gnulib-common.m4 | 159 |
1 files changed, 58 insertions, 101 deletions
diff --git a/m4/gnulib-common.m4 b/m4/gnulib-common.m4 index 3f74cb4d038..57b94ed5325 100644 --- a/m4/gnulib-common.m4 +++ b/m4/gnulib-common.m4 @@ -1,9 +1,11 @@ -# gnulib-common.m4 serial 38 +# gnulib-common.m4 serial 44 dnl Copyright (C) 2007-2019 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], [ @@ -14,12 +16,18 @@ AC_DEFUN([gl_COMMON], [ AC_DEFUN([gl_COMMON_BODY], [ 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))) +# define _Noreturn [[noreturn]] +# elif ((!defined __cplusplus || defined __clang__) \ + && (201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) \ + || 4 < __GNUC__ + (7 <= __GNUC_MINOR__))) + /* _Noreturn works as-is. */ +# elif 2 < __GNUC__ + (8 <= __GNUC_MINOR__) || 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 @@ -72,6 +80,40 @@ AC_DEFUN([gl_COMMON_BODY], [ #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 + <http://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 Preparation for running test programs: dnl Tell glibc to write diagnostics from -D_FORTIFY_SOURCE=2 to stderr, not @@ -207,13 +249,6 @@ 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. @@ -226,7 +261,6 @@ m4_ifndef([AS_VAR_IF], # Modifies the value of the shell variable CC in an attempt to make $CC # understand ISO C99 source code. # This is like AC_PROG_CC_C99, except that -# - AC_PROG_CC_C99 did not exist in Autoconf versions < 2.60, # - AC_PROG_CC_C99 does not mix well with AC_PROG_CC_STDC # <https://lists.gnu.org/r/bug-gnulib/2011-09/msg00367.html>, # but many more packages use AC_PROG_CC_STDC than AC_PROG_CC_C99 @@ -315,25 +349,6 @@ Amsterdam AC_SUBST([RANLIB]) ]) -# AC_PROG_MKDIR_P -# is a backport of autoconf-2.60's AC_PROG_MKDIR_P, with a fix -# for interoperability with automake-1.9.6 from autoconf-2.62. -# Remove this macro when we can assume autoconf >= 2.62 or -# autoconf >= 2.60 && automake >= 1.10. -# AC_AUTOCONF_VERSION was introduced in 2.62, so use that as the witness. -m4_ifndef([AC_AUTOCONF_VERSION],[ -m4_ifdef([AC_PROG_MKDIR_P], [ - dnl For automake-1.9.6 && autoconf < 2.62: Ensure MKDIR_P is AC_SUBSTed. - m4_define([AC_PROG_MKDIR_P], - m4_defn([AC_PROG_MKDIR_P])[ - AC_SUBST([MKDIR_P])])], [ - dnl For autoconf < 2.60: Backport of AC_PROG_MKDIR_P. - AC_DEFUN_ONCE([AC_PROG_MKDIR_P], - [AC_REQUIRE([AM_PROG_MKDIR_P])dnl defined by automake - MKDIR_P='$(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 @@ -347,16 +362,16 @@ AC_DEFUN([AC_C_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); - ]])], + [[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 @@ -407,61 +422,3 @@ AC_DEFUN([gl_CACHE_VAL_SILENT], # 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 - else - ac_cv_path_SED=$SED - fi - ]) - SED="$ac_cv_path_SED" - AC_SUBST([SED])dnl - rm -f conftest.sed -]) -]) |