X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=src%2Ffreeglut_callbacks.c;h=da06283cd91cc101d519677ce2a4eaaf8c9024e1;hb=c098c349121295f7ce55563cabc88e68c985fd99;hp=90baf105b5ad89ab4eac49e3661c90ef2808c17b;hpb=9b5ed2940eac112c894bb43f802fbda5b1c8b27a;p=freeglut

diff --git a/src/freeglut_callbacks.c b/src/freeglut_callbacks.c
index 90baf10..da06283 100644
--- a/src/freeglut_callbacks.c
+++ b/src/freeglut_callbacks.c
@@ -48,6 +48,9 @@
  */
 void FGAPIENTRY glutDisplayFunc( void (* callback)( void ) )
 {
+    if( !callback )
+	fgError ("Fatal error in program.  NULL display callback not "
+	    "permitted in GLUT 3.0+ or freeglut 2.0.1+\n");
     SET_CALLBACK( Display );
 
     /*