[llvm] r346985 - [ADT] Drop llvm::Optional clang-specific optmization for trivially copyable types

[Tom Stellard via llvm-commits]

Author: tstellar
Date: Thu Nov 15 11:32:24 2018
New Revision: 346985

URL: http://llvm.org/viewvc/llvm-project?rev=346985&view=rev
Log:
[ADT] Drop llvm::Optional clang-specific optmization for trivially copyable types

Summary:
This fixes libLLVM.so ABI mismatches between llvm compiled with clang
and llvm compiled with gcc (PR39427).

Reviewers: bkramer, sylvestre.ledru, mgorny, hans

Reviewed By: bkramer, hans

Subscribers: dexonsmith, kristina, llvm-commits

Differential Revision: https://reviews.llvm.org/D54540

Modified:
    llvm/trunk/include/llvm/ADT/Optional.h

Modified: llvm/trunk/include/llvm/ADT/Optional.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/ADT/Optional.h?rev=346985&r1=346984&r2=346985&view=diff
==============================================================================
--- llvm/trunk/include/llvm/ADT/Optional.h (original)
+++ llvm/trunk/include/llvm/ADT/Optional.h Thu Nov 15 11:32:24 2018
@@ -108,24 +108,6 @@ template <typename T, bool IsPodLike> st
   }
 };
 
-#if !defined(__GNUC__) || defined(__clang__) // GCC up to GCC7 miscompiles this.
-/// Storage for trivially copyable types only.
-template <typename T> struct OptionalStorage<T, true> {
-  AlignedCharArrayUnion<T> storage;
-  bool hasVal = false;
-
-  OptionalStorage() = default;
-
-  OptionalStorage(const T &y) : hasVal(true) { new (storage.buffer) T(y); }
-  OptionalStorage &operator=(const T &y) {
-    *reinterpret_cast<T *>(storage.buffer) = y;
-    hasVal = true;
-    return *this;
-  }
-
-  void reset() { hasVal = false; }
-};
-#endif
 } // namespace optional_detail
 
 template <typename T> class Optional {