1 # serial 8 -*- Autoconf -*- 2 # Enable extensions on systems that normally disable them. 3 4 # Copyright (C) 2003, 2006-2009 Free Software Foundation, Inc. 5 # This file is free software; the Free Software Foundation 6 # gives unlimited permission to copy and/or distribute it, 7 # with or without modifications, as long as this notice is preserved. 8 9 # This definition of AC_USE_SYSTEM_EXTENSIONS is stolen from CVS 10 # Autoconf. Perhaps we can remove this once we can assume Autoconf 11 # 2.62 or later everywhere, but since CVS Autoconf mutates rapidly 12 # enough in this area it's likely we'll need to redefine 13 # AC_USE_SYSTEM_EXTENSIONS for quite some time. 14 15 # AC_USE_SYSTEM_EXTENSIONS 16 # ------------------------ 17 # Enable extensions on systems that normally disable them, 18 # typically due to standards-conformance issues. 19 # Remember that #undef in AH_VERBATIM gets replaced with #define by 20 # AC_DEFINE. The goal here is to define all known feature-enabling 21 # macros, then, if reports of conflicts are made, disable macros that 22 # cause problems on some platforms (such as __EXTENSIONS__). 23 AC_DEFUN_ONCE([AC_USE_SYSTEM_EXTENSIONS], 24 [AC_BEFORE([$0], [AC_COMPILE_IFELSE])dnl 25 AC_BEFORE([$0], [AC_RUN_IFELSE])dnl 26 27 AC_REQUIRE([AC_CANONICAL_HOST]) 28 29 AC_CHECK_HEADER([minix/config.h], [MINIX=yes], [MINIX=]) 30 if test "$MINIX" = yes; then 31 AC_DEFINE([_POSIX_SOURCE], [1], 32 [Define to 1 if you need to in order for `stat' and other 33 things to work.]) 34 AC_DEFINE([_POSIX_1_SOURCE], [2], 35 [Define to 2 if the system does not provide POSIX.1 features 36 except with this defined.]) 37 AC_DEFINE([_MINIX], [1], 38 [Define to 1 if on MINIX.]) 39 fi 40 41 dnl HP-UX 11.11 defines mbstate_t only if _XOPEN_SOURCE is defined to 500, 42 dnl regardless of whether the flags -Ae or _D_HPUX_SOURCE=1 are already 43 dnl provided. 44 case "$host_os" in 45 hpux*) 46 AC_DEFINE([_XOPEN_SOURCE], [500], 47 [Define to 500 only on HP-UX.]) 48 ;; 49 esac 50 51 AH_VERBATIM([__EXTENSIONS__], 52 [/* Enable extensions on AIX 3, Interix. */ 53 #ifndef _ALL_SOURCE 54 # undef _ALL_SOURCE 55 #endif 56 /* Enable GNU extensions on systems that have them. */ 57 #ifndef _GNU_SOURCE 58 # undef _GNU_SOURCE 59 #endif 60 /* Enable threading extensions on Solaris. */ 61 #ifndef _POSIX_PTHREAD_SEMANTICS 62 # undef _POSIX_PTHREAD_SEMANTICS 63 #endif 64 /* Enable extensions on HP NonStop. */ 65 #ifndef _TANDEM_SOURCE 66 # undef _TANDEM_SOURCE 67 #endif 68 /* Enable general extensions on Solaris. */ 69 #ifndef __EXTENSIONS__ 70 # undef __EXTENSIONS__ 71 #endif 72 ]) 73 AC_CACHE_CHECK([whether it is safe to define __EXTENSIONS__], 74 [ac_cv_safe_to_define___extensions__], 75 [AC_COMPILE_IFELSE( 76 [AC_LANG_PROGRAM([[ 77 # define __EXTENSIONS__ 1 78 ]AC_INCLUDES_DEFAULT])], 79 [ac_cv_safe_to_define___extensions__=yes], 80 [ac_cv_safe_to_define___extensions__=no])]) 81 test $ac_cv_safe_to_define___extensions__ = yes && 82 AC_DEFINE([__EXTENSIONS__]) 83 AC_DEFINE([_ALL_SOURCE]) 84 AC_DEFINE([_GNU_SOURCE]) 85 AC_DEFINE([_POSIX_PTHREAD_SEMANTICS]) 86 AC_DEFINE([_TANDEM_SOURCE]) 87 ])# AC_USE_SYSTEM_EXTENSIONS 88 89 # gl_USE_SYSTEM_EXTENSIONS 90 # ------------------------ 91 # Enable extensions on systems that normally disable them, 92 # typically due to standards-conformance issues. 93 AC_DEFUN_ONCE([gl_USE_SYSTEM_EXTENSIONS], 94 [ 95 dnl Require this macro before AC_USE_SYSTEM_EXTENSIONS. 96 dnl gnulib does not need it. But if it gets required by third-party macros 97 dnl after AC_USE_SYSTEM_EXTENSIONS is required, autoconf 2.62..2.63 emit a 98 dnl warning: "AC_COMPILE_IFELSE was called before AC_USE_SYSTEM_EXTENSIONS". 99 dnl Note: We can do this only for one of the macros AC_AIX, AC_GNU_SOURCE, 100 dnl AC_MINIX. If people still use AC_AIX or AC_MINIX, they are out of luck. 101 AC_REQUIRE([AC_GNU_SOURCE]) 102 103 AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS]) 104 ]) 105
