added autoconf macro AC_C_RESTRICT

configure

@@ -12354,6 +12354,52 @@ fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for C/C++ restrict keyword" >&5
+$as_echo_n "checking for C/C++ restrict keyword... " >&6; }
+if ${ac_cv_c_restrict+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_cv_c_restrict=no
+   # The order here caters to the fact that C++ does not require restrict.
+   for ac_kw in __restrict __restrict__ _Restrict restrict; do
+     cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+typedef int * int_ptr;
+	int foo (int_ptr $ac_kw ip) {
+	return ip[0];
+       }
+int
+main ()
+{
+int s[1];
+	int * $ac_kw t = s;
+	t[0] = 0;
+	return foo(t)
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  ac_cv_c_restrict=$ac_kw
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+     test "$ac_cv_c_restrict" != no && break
+   done
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_c_restrict" >&5
+$as_echo "$ac_cv_c_restrict" >&6; }
+
+ case $ac_cv_c_restrict in
+   restrict) ;;
+   no) $as_echo "#define restrict /**/" >>confdefs.h
+ ;;
+   *)  cat >>confdefs.h <<_ACEOF
+#define restrict $ac_cv_c_restrict
+_ACEOF
+ ;;
+ esac
+
 ac_ext=${ac_fc_srcext-f}
 ac_compile='$FC -c $FCFLAGS $ac_fcflags_srcext conftest.$ac_ext >&5'
 ac_link='$FC -o conftest$ac_exeext $FCFLAGS $LDFLAGS $ac_fcflags_srcext conftest.$ac_ext $LIBS >&5'

configure.ac

@@ -27,6 +27,7 @@ LT_INIT([pic-only])
 AC_CHECK_TOOL([CC],[gcc],[:])
 AC_PROG_CC_C99
 AM_PROG_CC_C_O
+AC_C_RESTRICT
 AC_PROG_FC
 AS_IF([test -n "$FC" && test "X$FC" != "Xno"],
   [AC_FC_SRCEXT([f90])

src/config.h.in

@@ -260,3 +260,17 @@
 
 /* Defined to return type of backtrace(). */
 #undef backtrace_size_t
+
+/* 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 or
+   __restrict__, even though the corresponding Sun C compiler ends up with
+   "#define restrict _Restrict" or "#define restrict __restrict__" in the
+   previous line.  Perhaps some future version of Sun C++ will work with
+   restrict; if so, hopefully it defines __RESTRICT like Sun C does.  */
+#if defined __SUNPRO_CC && !defined __RESTRICT
+# define _Restrict
+# define __restrict__
+#endif