build fixes, rh9
diff --git a/progs/tests/dinoshade.c b/progs/tests/dinoshade.c
index e3086bb..1e4d4ab 100644
--- a/progs/tests/dinoshade.c
+++ b/progs/tests/dinoshade.c
@@ -38,6 +38,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <math.h>       /* for cos(), sin(), and sqrt() */
+#include <malloc.h>	/* for ptrdiff_t, referenced by GL.h when GL_GLEXT_LEGACY defined */
 #ifdef _WIN32
 #include <windows.h>
 #endif