1 files changed, 15 insertions, 0 deletions
diff --git a/m4/cflags.m4 b/m4/cflags.m4
new file mode 100644
index 000000000..cc6d5fab3
--- /dev/null
+++ b/m4/cflags.m4
@@ -0,0 +1,15 @@
+AC_DEFUN([CHECK_CFLAG], [
+    var=`echo "$1" | tr "=-" "__"`
+    AC_CACHE_CHECK([whether the C compiler accepts $1],[check_cflag_$var],[
+        save_CFLAGS="$CFLAGS"
+        CFLAGS="$CFLAGS $1"
+        AC_COMPILE_IFELSE([int main(void) { return 0; }],
+            [eval "check_cflag_$var=yes"],
+            [eval "check_cflag_$var=no"])
+        CFLAGS="$save_CFLAGS"
+        ])
+    if eval "test x`echo '$check_cflag_'$var` = xyes"; then
+        AM_CFLAGS="$AM_CFLAGS $1"
+    fi
+    ])
+])