From 19fde548419e29975963d2c325710f532fba4022 Mon Sep 17 00:00:00 2001
From: Andrew Kryczka <andrewkr@fb.com>
Date: Tue, 1 May 2018 13:18:01 -0700
Subject: [PATCH] initialize local variable for UBSAN in PosixEnv function

Summary:
this is a repeat commit of a8a28da2159648a2f72c35ea507371df8a97a2a9, which got reverted together with 6afe22db2e667799d8c903db61750d676bffe152, but forgotten about when that commit was un-reverted in 46152d53bf58748fc3ed0681d8970c342bcfc47a.
Closes https://github.com/facebook/rocksdb/pull/3796

Differential Revision: D7826077

Pulled By: ajkr

fbshipit-source-id: edb22375da56e2feda50c5b35f942f4d2d52b19c
---
 env/env_posix.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/env/env_posix.cc b/env/env_posix.cc
index a9895ec78..038d7c44a 100644
--- a/env/env_posix.cc
+++ b/env/env_posix.cc
@@ -479,7 +479,7 @@ class PosixEnv : public Env {
     if (status.ok()) {
       status = GetFileSize(fname, &size);
     }
-    void* base;
+    void* base = nullptr;
     if (status.ok()) {
       base = mmap(nullptr, static_cast<size_t>(size), PROT_READ | PROT_WRITE,
                   MAP_SHARED, fd, 0);