From dc10aeeff853c2156c1290144d5a004e03b91b76 Mon Sep 17 00:00:00 2001
From: Josh Bleecher Snyder <josharian@gmail.com>
Date: Sat, 26 Aug 2017 06:55:34 -0700
Subject: [PATCH] runtime: only clear key string's pointer in mapdelete_faststr

Change-Id: I0360d294868ec4423e4ae036009fac4e72425c9c
Reviewed-on: https://go-review.googlesource.com/59152
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
---
 src/runtime/hashmap_fast.go | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/runtime/hashmap_fast.go b/src/runtime/hashmap_fast.go
index c378647892..f117311439 100644
--- a/src/runtime/hashmap_fast.go
+++ b/src/runtime/hashmap_fast.go
@@ -754,7 +754,8 @@ search:
 			if k.str != key.str && !memequal(k.str, key.str, uintptr(key.len)) {
 				continue
 			}
-			*(*string)(kptr) = ""
+			// Clear key's pointer.
+			k.str = nil
 			// Only clear value if there are pointers in it.
 			if t.elem.kind&kindNoPointers == 0 {
 				v := add(unsafe.Pointer(b), dataOffset+bucketCnt*2*sys.PtrSize+i*uintptr(t.valuesize))
-- 
2.50.0