gc: multiple return value at top-level invoked multiple times

Fixes #402.

R=ken2
CC=golang-dev
https://golang.org/cl/186214

src/cmd/gc/sinit.c

@@ -90,12 +90,18 @@ init1(Node *n, NodeList **out)
 			break;
 		
 		case OAS2FUNC:
+			if(n->defn->initorder)
+				break;
+			n->defn->initorder = 1;
 			for(l=n->defn->rlist; l; l=l->next)
 				init1(l->n, out);
 			*out = list(*out, n->defn);
 			break;
 		
 		case OAS2MAPR:
+			if(n->defn->initorder)
+				break;
+			n->defn->initorder = 1;
 			for(l=n->defn->rlist; l; l=l->next)
 				init1(l->n, out);
 			*out = list(*out, n->defn);

test/fixedbugs/bug244.go

+// $G $D/$F.go && $L $F.$A && ./$A.out
+
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+var nf int
+var ng int
+
+func f() (int, int, int) {
+	nf++
+	return 1, 2, 3
+}
+
+func g() int {
+	ng++
+	return 4
+}
+
+var x, y, z = f()
+var m = make(map[int]int)
+var v, ok = m[g()]
+
+func main() {
+	if x != 1 || y != 2 || z != 3 || nf != 1 || v != 0 || ok != false || ng != 1 {
+		panic("x=", x, " y=", y, " z=", z, " nf=", nf, " v=", v, " ok=", ok, " ng=", ng)
+	}
+}