From: Louis Brandy <ldbrandy@fb.com>
Date: Sat, 8 Apr 2017 02:25:07 +0000 (-0700)
Subject: fix EvictingCacheMap test bug found w/ -fsanitize-address-use-after-scope
X-Git-Tag: v2017.04.10.00~6
X-Git-Url: http://plrg.eecs.uci.edu/git/?p=folly.git;a=commitdiff_plain;h=6ea7629b0091ebd0284106cdbfee36b80619b62f

fix EvictingCacheMap test bug found w/ -fsanitize-address-use-after-scope

Summary: This test actually stores references to `sum` in objects it puts into the `EvictingCacheMap`. Those references get accessed in the destructor of the objects, which is the destructor of the `EvictingCacheMap`. That means the `sum` variable must outlive (and be declared -before-) the `EvictingCacheMap` it's testing.

Reviewed By: yfeldblum, meyering

Differential Revision: D4854619

fbshipit-source-id: b0a3109278f48d10b4cd0c52a12cb2064f4a00c5
---

diff --git a/folly/test/EvictingCacheMapTest.cpp b/folly/test/EvictingCacheMapTest.cpp
index cac07641..85a4a5ed 100644
--- a/folly/test/EvictingCacheMapTest.cpp
+++ b/folly/test/EvictingCacheMapTest.cpp
@@ -317,15 +317,15 @@ TEST(EvictingCacheMap, DestructorInvocationTest) {
     int* ref;
   };
 
+  int sum;
   EvictingCacheMap<int, SumInt> map(0);
+
   EXPECT_EQ(0, map.size());
   EXPECT_TRUE(map.empty());
   for (int i = 0; i < 100; i++) {
     EXPECT_FALSE(map.exists(i));
   }
 
-  int sum;
-
   for (int i = 0; i < 100; i++) {
     map.set(i, SumInt(i, &sum));
     EXPECT_EQ(i + 1, map.size());