Prefer uninitialized memory for scratch space.

No functional change intended.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@234184 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Basic/SourceManager.cpp

@@ -110,8 +110,8 @@ llvm::MemoryBuffer *ContentCache::getBuffer(DiagnosticsEngine &Diag,
   // possible.
   if (!BufferOrError) {
     StringRef FillStr("<<<MISSING SOURCE FILE>>>\n");
-    Buffer.setPointer(MemoryBuffer::getNewMemBuffer(ContentsEntry->getSize(),
-                                                    "<invalid>").release());
+    Buffer.setPointer(MemoryBuffer::getNewUninitMemBuffer(
+                          ContentsEntry->getSize(), "<invalid>").release());
     char *Ptr = const_cast<char*>(Buffer.getPointer()->getBufferStart());
     for (unsigned i = 0, e = ContentsEntry->getSize(); i != e; ++i)
       Ptr[i] = FillStr[i % FillStr.size()];

lib/Lex/ScratchBuffer.cpp

@@ -65,7 +65,7 @@ void ScratchBuffer::AllocScratchBuffer(unsigned RequestLen) {
     RequestLen = ScratchBufSize;
 
   std::unique_ptr<llvm::MemoryBuffer> OwnBuf =
-      llvm::MemoryBuffer::getNewMemBuffer(RequestLen, "<scratch space>");
+      llvm::MemoryBuffer::getNewUninitMemBuffer(RequestLen, "<scratch space>");
   llvm::MemoryBuffer &Buf = *OwnBuf;
   FileID FID = SourceMgr.createFileID(std::move(OwnBuf));
   BufferStartLoc = SourceMgr.getLocForStartOfFile(FID);