1 dnl Provide AC_USE_SYSTEM_EXTENSIONS for old autoconf machines.
2 AC_DEFUN([ACX_USE_SYSTEM_EXTENSIONS],[
3 ifdef([AC_USE_SYSTEM_EXTENSIONS],[
4 AC_USE_SYSTEM_EXTENSIONS
6 AC_BEFORE([$0], [AC_COMPILE_IFELSE])
7 AC_BEFORE([$0], [AC_RUN_IFELSE])
9 AC_REQUIRE([AC_GNU_SOURCE])
11 AC_REQUIRE([AC_MINIX])
13 AH_VERBATIM([__EXTENSIONS__],
14 [/* Enable extensions on Solaris. */
15 #ifndef __EXTENSIONS__
16 # undef __EXTENSIONS__
18 #ifndef _POSIX_PTHREAD_SEMANTICS
19 # undef _POSIX_PTHREAD_SEMANTICS
21 #ifndef _TANDEM_SOURCE
22 # undef _TANDEM_SOURCE
24 AC_CACHE_CHECK([whether it is safe to define __EXTENSIONS__],
25 [ac_cv_safe_to_define___extensions__],
28 # define __EXTENSIONS__ 1
29 AC_INCLUDES_DEFAULT])],
30 [ac_cv_safe_to_define___extensions__=yes],
31 [ac_cv_safe_to_define___extensions__=no])])
32 test $ac_cv_safe_to_define___extensions__ = yes &&
33 AC_DEFINE([__EXTENSIONS__])
34 AC_DEFINE([_POSIX_PTHREAD_SEMANTICS])
35 AC_DEFINE([_TANDEM_SOURCE])