From 5b62ba14c460a23d31c8c2645a41c196ceee8220 Mon Sep 17 00:00:00 2001
From: Anthony Martin <ality@pbrane.org>
Date: Tue, 31 May 2011 15:41:47 -0400
Subject: [PATCH] gc: disallow ... in type conversions

Fixes #1866.

R=bradfitz, rsc
CC=golang-dev
https://golang.org/cl/4548073
---
 src/cmd/gc/typecheck.c | 2 +-
 test/ddd1.go           | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/cmd/gc/typecheck.c b/src/cmd/gc/typecheck.c
index 0cf11684da..66fc77a973 100644
--- a/src/cmd/gc/typecheck.c
+++ b/src/cmd/gc/typecheck.c
@@ -794,7 +794,7 @@ reswitch:
 		defaultlit(&n->left, T);
 		l = n->left;
 		if(l->op == OTYPE) {
-			if(n->isddd)
+			if(n->isddd || l->type->bound == -100)
 				yyerror("invalid use of ... in type conversion", l);
 			// pick off before type-checking arguments
 			ok |= Erv;
diff --git a/test/ddd1.go b/test/ddd1.go
index a0bc73814f..96a358e1c0 100644
--- a/test/ddd1.go
+++ b/test/ddd1.go
@@ -43,4 +43,5 @@ func bad(args ...int) {
 	var x int
 	_ = unsafe.Pointer(&x...)	// ERROR "[.][.][.]"
 	_ = unsafe.Sizeof(x...)	// ERROR "[.][.][.]"
+	_ = [...]byte("foo") // ERROR "[.][.][.]"
 }
-- 
2.48.1