1# Enable extensions on systems that normally disable them. 2 3# Copyright (C) 2003, 2006 Free Software Foundation, Inc. 4# This file is free software; the Free Software Foundation 5# gives unlimited permission to copy and/or distribute it, 6# with or without modifications, as long as this notice is preserved. 7 8# This file is only needed in autoconf <= 2.59. Newer versions of autoconf 9# have a macro AC_USE_SYSTEM_EXTENSIONS with identical semantics. 10 11# gl_USE_SYSTEM_EXTENSIONS 12# ------------------------ 13# Enable extensions on systems that normally disable them, 14# typically due to standards-conformance issues. 15AC_DEFUN([gl_USE_SYSTEM_EXTENSIONS], [ 16 AC_BEFORE([$0], [AC_COMPILE_IFELSE]) 17 AC_BEFORE([$0], [AC_RUN_IFELSE]) 18 19 AC_REQUIRE([AC_GNU_SOURCE]) 20 AC_REQUIRE([AC_AIX]) 21 AC_REQUIRE([AC_MINIX]) 22 23 AH_VERBATIM([__EXTENSIONS__], 24[/* Enable extensions on Solaris. */ 25#ifndef __EXTENSIONS__ 26# undef __EXTENSIONS__ 27#endif 28#ifndef _POSIX_PTHREAD_SEMANTICS 29# undef _POSIX_PTHREAD_SEMANTICS 30#endif]) 31 AC_CACHE_CHECK([whether it is safe to define __EXTENSIONS__], 32 [ac_cv_safe_to_define___extensions__], 33 [AC_COMPILE_IFELSE( 34 [AC_LANG_PROGRAM([ 35 #define __EXTENSIONS__ 1 36 AC_INCLUDES_DEFAULT])], 37 [ac_cv_safe_to_define___extensions__=yes], 38 [ac_cv_safe_to_define___extensions__=no])]) 39 test $ac_cv_safe_to_define___extensions__ = yes && 40 AC_DEFINE([__EXTENSIONS__]) 41 AC_DEFINE([_POSIX_PTHREAD_SEMANTICS]) 42]) 43