From f7c27b9af9823baad0c2bb34d036d8991ac587e6 Mon Sep 17 00:00:00 2001
From: Robert Griesemer <gri@golang.org>
Date: Thu, 11 Mar 2010 17:39:55 -0800
Subject: [PATCH] ast/filter.go: missing nil-check causes crash

R=rsc
CC=golang-dev
https://golang.org/cl/461041
---
 src/pkg/go/ast/filter.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/pkg/go/ast/filter.go b/src/pkg/go/ast/filter.go
index 1c2aea3574..4e2060303b 100644
--- a/src/pkg/go/ast/filter.go
+++ b/src/pkg/go/ast/filter.go
@@ -293,7 +293,7 @@ func MergePackageFiles(pkg *Package, complete bool) *File {
 						name := f.Name.Name()
 						if j, exists := funcs[name]; exists {
 							// function declared already
-							if decls[j].(*FuncDecl).Doc == nil {
+							if decls[j] != nil && decls[j].(*FuncDecl).Doc == nil {
 								// existing declaration has no documentation;
 								// ignore the existing declaration
 								decls[j] = nil