bug 100 - spurious return warnings

R=r
OCL=15221
CL=15221

test/bugs/bug100.go

+// Copyright 2009 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.
+
+// $G $D/$F.go || (echo BUG: should compile cleanly; exit 1)
+package main
+
+func f() int {
+	i := 0
+	for {
+		if i >= sys.argc() {
+			return i
+		}
+		i++
+	}
+}
+
+func g() int {
+	for {
+	}
+}
+
+func h() int {
+	for {
+		return 1
+	}
+}