diff --git a/configure.ac b/configure.ac
index 278cf36bf..451858f74 100644
--- a/configure.ac
+++ b/configure.ac
@@ -12,7 +12,7 @@ AC_SUBST(MP4FF_LIB)
 AC_SUBST(MP4FF_SUBDIR)
 
 AC_LANG(C)
-AC_PROG_CC
+AC_PROG_CC_C99
 AM_PROG_CC_C_O
 AC_PROG_INSTALL
 AC_PROG_LIBTOOL