diff --git a/cde/config/imake/ccimake.c b/cde/config/imake/ccimake.c
index 57ccf6a8a..db76b5894 100644
--- a/cde/config/imake/ccimake.c
+++ b/cde/config/imake/ccimake.c
@@ -56,6 +56,8 @@ in this Software without prior written authorization from The Open Group .
 #define imake_ccflags "-O"
 #endif
 
+#include <stdlib.h>
+
 main()
 {
 	write(1, imake_ccflags, sizeof(imake_ccflags) - 1);