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-rw-r--r--gl/m4/gnulib-common.m445
1 files changed, 44 insertions, 1 deletions
diff --git a/gl/m4/gnulib-common.m4 b/gl/m4/gnulib-common.m4
index 53980108..9336d726 100644
--- a/gl/m4/gnulib-common.m4
+++ b/gl/m4/gnulib-common.m4
@@ -1,4 +1,4 @@
-# gnulib-common.m4 serial 2
+# gnulib-common.m4 serial 3
dnl Copyright (C) 2007 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
@@ -20,3 +20,46 @@ m4_ifdef([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 overrides the AC_C_RESTRICT macro from autoconf 2.60..2.61,
+# so that mixed use of GNU C and GNU C++ and mixed use of Sun C and Sun C++
+# works.
+# This definition can be removed once autoconf >= 2.62 can be assumed.
+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 s[1];
+ int * $ac_kw t = s;
+ t[0] = 0;
+ return foo(t)]])],
+ [ac_cv_c_restrict=$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 Sun C++: it does not support _Restrict, even
+ though the corresponding Sun C compiler does, which causes
+ "#define restrict _Restrict" in the previous line. Perhaps some future
+ version of Sun C++ will work with _Restrict; if so, it'll probably
+ define __RESTRICT, just as Sun C does. */
+#if defined __SUNPRO_CC && !defined __RESTRICT
+# define _Restrict
+#endif])
+ case $ac_cv_c_restrict in
+ restrict) ;;
+ no) AC_DEFINE([restrict], []) ;;
+ *) AC_DEFINE_UNQUOTED([restrict], [$ac_cv_c_restrict]) ;;
+ esac
+])