Fix undefined behavior when compiling in C++14 mode (with sized deletion

enabled): ensure that we do not invoke the sized deallocator for MemoryBuffer
subclasses that have tail-allocated data.

llvm-svn: 259735

1 files changed, 8 insertions, 0 deletions

diff --git a/llvm/lib/Support/MemoryBuffer.cpp b/llvm/lib/Support/MemoryBuffer.cpp
index 25ddfe52a1d..b935cbf1ae7 100644
--- a/llvm/lib/Support/MemoryBuffer.cpp
+++ b/llvm/lib/Support/MemoryBuffer.cpp
@@ -86,6 +86,10 @@ public:
     init(InputData.begin(), InputData.end(), RequiresNullTerminator);
   }
 
+  /// Disable sized deallocation for MemoryBufferMem, because it has
+  /// tail-allocated data.
+  void operator delete(void *p) { ::operator delete(p); }
+
   const char *getBufferIdentifier() const override {
      // The name is stored after the class itself.
     return reinterpret_cast<const char*>(this + 1);
@@ -213,6 +217,10 @@ public:
     }
   }
 
+  /// Disable sized deallocation for MemoryBufferMMapFile, because it has
+  /// tail-allocated data.
+  void operator delete(void *p) { ::operator delete(p); }
+
   const char *getBufferIdentifier() const override {
     // The name is stored after the class itself.
     return reinterpret_cast<const char *>(this + 1);