progs: Get more samples building on windows.
diff --git a/progs/demos/multiarb.c b/progs/demos/multiarb.c
index 451fd11..85c4e3a 100644
--- a/progs/demos/multiarb.c
+++ b/progs/demos/multiarb.c
@@ -14,6 +14,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <GL/glew.h>
 #include <GL/glut.h>
 
 #include "readtex.h"
@@ -326,6 +327,7 @@
    glutInitWindowPosition( 0, 0 );
    glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE );
    glutCreateWindow(argv[0] );
+   glewInit();
 
    Init( argc, argv );