diff --git a/configure.in b/configure.in
index cd08ef62..d2acc146 100644
--- a/configure.in
+++ b/configure.in
@@ -43,6 +43,7 @@ AH_TEMPLATE([TARGET_CPU], [Target CPU name])
 # -- C Compiler --
 
 AC_PROG_CC
+AC_C_PROTOTYPES
 
 # -- Helper programs --