From: Luuk van Dijk <lvd@golang.org>
Date: Tue, 10 Jan 2012 10:07:35 +0000 (+0100)
Subject: gc: omit runtime.closure wrap for closures without closure variables
X-Git-Tag: weekly.2012-01-15~100
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=ba25778f3f24fcf0be5167737b28dd62d7fbeff1;p=gostls13.git

gc: omit runtime.closure wrap for closures without closure variables

Fixes #1894.

test/closure.go's test for newfunc already covers this.

R=rsc, dsymonds, bradfitz
CC=golang-dev
https://golang.org/cl/5516051
---

diff --git a/src/cmd/gc/closure.c b/src/cmd/gc/closure.c
index d29e8cbc28..fa44e40fae 100644
--- a/src/cmd/gc/closure.c
+++ b/src/cmd/gc/closure.c
@@ -192,6 +192,10 @@ walkclosure(Node *func, NodeList **init)
 	Node *xtype, *xfunc, *call, *clos;
 	NodeList *l, *in;
 
+	// no closure vars, don't bother wrapping
+	if(func->cvars == nil)
+		return makeclosure(func, init, 1)->nname;
+
 	/*
 	 * wrap body in external function
 	 * with extra closure parameters.