Replace __extension__ with LONGSTRING.
diff --git a/src/mesa/shader/arbprogparse.c b/src/mesa/shader/arbprogparse.c
index 5a61f30..72d4909 100644
--- a/src/mesa/shader/arbprogparse.c
+++ b/src/mesa/shader/arbprogparse.c
@@ -3703,7 +3703,7 @@
 
 
 /* XXX temporary */
-__extension__ static char core_grammar_text[] =
+LONGSTRING static char core_grammar_text[] =
 #include "grammar_syn.h"
 ;