From 73653841af0ec9da0037e412d07ecff24d014494 Mon Sep 17 00:00:00 2001
From: Russ Cox <rsc@golang.org>
Date: Thu, 11 Dec 2008 15:56:13 -0800
Subject: [PATCH] reject struct to interface conversion for now

R=ken
OCL=21007
CL=21007
---
 src/cmd/gc/walk.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/cmd/gc/walk.c b/src/cmd/gc/walk.c
index d31b1269a2..c0b78d69df 100644
--- a/src/cmd/gc/walk.c
+++ b/src/cmd/gc/walk.c
@@ -2733,7 +2733,12 @@ isandss(Type *lt, Node *r)
 				return I2I;
 			return Inone;
 		}
-		if(isnilinter(lt) || ismethod(rt) != T)
+		if(isnilinter(lt)) {
+			if(!issimple[rt->etype] && !isptr[rt->etype])
+				yyerror("using %T as interface is unimplemented", rt);
+			return T2I;
+		}
+		if(ismethod(rt) != T)
 			return T2I;
 		return Inone;
 	}
-- 
2.48.1