[lld] 99f0236 - [PDB] Fix ubsan complaint about memcpy from null pointer

[Reid Kleckner via llvm-commits]

Author: Reid Kleckner
Date: 2021-05-27T19:49:09-07:00
New Revision: 99f023656b785b79253dd1ddae6aa2f822180aab

URL: https://github.com/llvm/llvm-project/commit/99f023656b785b79253dd1ddae6aa2f822180aab
DIFF: https://github.com/llvm/llvm-project/commit/99f023656b785b79253dd1ddae6aa2f822180aab.diff

LOG: [PDB] Fix ubsan complaint about memcpy from null pointer

Added: 
    

Modified: 
    lld/COFF/DebugTypes.cpp

Removed: 
    


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diff  --git a/lld/COFF/DebugTypes.cpp b/lld/COFF/DebugTypes.cpp
index 69b031e9a2d5..bda9b7728d95 100644
--- a/lld/COFF/DebugTypes.cpp
+++ b/lld/COFF/DebugTypes.cpp
@@ -594,6 +594,8 @@ void TpiSource::loadGHashes() {
 // memory usage.
 void TpiSource::assignGHashesFromVector(
     std::vector<GloballyHashedType> &&hashVec) {
+  if (hashVec.empty())
+    return;
   GloballyHashedType *hashes = new GloballyHashedType[hashVec.size()];
   memcpy(hashes, hashVec.data(), hashVec.size() * sizeof(GloballyHashedType));
   ghashes = makeArrayRef(hashes, hashVec.size());