diff --git a/configure.ac b/configure.ac
index 78621042d..5984b667e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -462,7 +462,7 @@ dnl We want these before the checks, so the checks can modify their values.
 test -z "${CFLAGS+set}"  && CFLAGS=  auto_cflags=1
 test -z "${LDFLAGS+set}" && LDFLAGS= auto_ldflags=1
 
-AC_PROG_CC
+AC_PROG_CC_C99
 
 dnl Check for large file support.