From: Alexey Samsonov <vonosmas@gmail.com>
Date: Thu, 4 Dec 2014 23:00:50 +0000 (+0000)
Subject: Revert "Fix UBSan report in StringMap implementation."
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=59d867405a689e72baa9d104efabf8911526aea9;p=oota-llvm.git

Revert "Fix UBSan report in StringMap implementation."

This reverts commit r223402. Some bots fail with -Winvalid-offsetof
warning.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223407 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/llvm/ADT/StringMap.h b/include/llvm/ADT/StringMap.h
index 06afe842691..2feb2ab0074 100644
--- a/include/llvm/ADT/StringMap.h
+++ b/include/llvm/ADT/StringMap.h
@@ -182,7 +182,10 @@ public:
   /// GetStringMapEntryFromValue - Given a value that is known to be embedded
   /// into a StringMapEntry, return the StringMapEntry itself.
   static StringMapEntry &GetStringMapEntryFromValue(ValueTy &V) {
-    char *Ptr = reinterpret_cast<char *>(&V) - offsetof(StringMapEntry, second);
+    StringMapEntry *EPtr = 0;
+    char *Ptr = reinterpret_cast<char*>(&V) -
+                  (reinterpret_cast<char*>(&EPtr->second) -
+                   reinterpret_cast<char*>(EPtr));
     return *reinterpret_cast<StringMapEntry*>(Ptr);
   }
   static const StringMapEntry &GetStringMapEntryFromValue(const ValueTy &V) {