diff --git a/configure.ac b/configure.ac
index d7330234..4f14ebd0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1128,7 +1128,7 @@ fi
 if test "${enable_pedantic}" = "yes"; then
 	enable_strict="yes"
 	CFLAGS="${CFLAGS} -pedantic"
-	test "${WIN32}" != "yes" && CFLAGS="${CFLAGS} -ansi"
+	test "${WIN32}" != "yes" && CFLAGS="${CFLAGS} -std=c99"
 fi
 if test "${enable_strict}" = "yes"; then
 	CFLAGS="${CFLAGS} -Wall -Wno-unused-parameter -Wno-unused-function"