diff --git a/src/mesa/slang/slang_utility.h b/src/mesa/slang/slang_utility.h
index 2c0d0bcbb2a..cb9b6d2aaaa 100644
--- a/src/mesa/slang/slang_utility.h
+++ b/src/mesa/slang/slang_utility.h
@@ -26,6 +26,8 @@
 #define SLANG_UTILITY_H
 
 
+#include "main/glheader.h"
+
 /* Compile-time assertions.  If the expression is zero, try to declare an
  * array of size [-1] to cause compilation error.
  */