From a91a0a6a7a319425d29a47ab7900c432d6f648e4 Mon Sep 17 00:00:00 2001
From: Ken Thompson <ken@golang.org>
Date: Fri, 19 Dec 2008 14:26:52 -0800
Subject: [PATCH] array compare (except = != nil) are illegal

R=r
OCL=21637
CL=21637
---
 src/cmd/6g/cgen.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/cmd/6g/cgen.c b/src/cmd/6g/cgen.c
index c0a665c072..e735858808 100644
--- a/src/cmd/6g/cgen.c
+++ b/src/cmd/6g/cgen.c
@@ -751,6 +751,11 @@ bgen(Node *n, int true, Prog *to)
 		}
 
 		if(isdarray(nl->type)) {
+			// only valid to cmp darray to literal nil
+			if((a != OEQ && a != ONE) || nr->op != OLITERAL) {
+				yyerror("illegal array comparison");
+				break;
+			}
 			a = optoas(a, types[tptr]);
 			regalloc(&n1, types[tptr], N);
 			agen(nl, &n1);
-- 
2.48.1