1 files changed, 17 insertions, 0 deletions
diff --git a/llvm/lib/DebugInfo/PDB/Native/PDBFileBuilder.cpp b/llvm/lib/DebugInfo/PDB/Native/PDBFileBuilder.cpp
index dee27c621fa..1cb890ff799 100644
--- a/llvm/lib/DebugInfo/PDB/Native/PDBFileBuilder.cpp
+++ b/llvm/lib/DebugInfo/PDB/Native/PDBFileBuilder.cpp
@@ -178,6 +178,8 @@ Error PDBFileBuilder::commit(StringRef Filename) {
   auto OutFileOrError = FileOutputBuffer::create(Filename, Filesize);
   if (auto E = OutFileOrError.takeError())
     return E;
+  FileOutputBuffer *FOB = OutFileOrError->get();
+
   FileBufferByteStream Buffer(std::move(*OutFileOrError),
                               llvm::support::little);
   BinaryStreamWriter Writer(Buffer);
@@ -242,5 +244,20 @@ Error PDBFileBuilder::commit(StringRef Filename) {
       return EC;
   }
 
+  auto InfoStreamBlocks = Layout.StreamMap[StreamPDB];
+  assert(!InfoStreamBlocks.empty());
+  uint64_t InfoStreamFileOffset =
+      blockToOffset(InfoStreamBlocks.front(), Layout.SB->BlockSize);
+  InfoStreamHeader *H = reinterpret_cast<InfoStreamHeader *>(
+      FOB->getBufferStart() + InfoStreamFileOffset);
+
+  // Set the build id at the very end, after every other byte of the PDB
+  // has been written.
+  // FIXME: Use a hash of the PDB rather than time(nullptr) for the signature.
+  H->Age = Info->getAge();
+  H->Guid = Info->getGuid();
+  Optional<uint32_t> Sig = Info->getSignature();
+  H->Signature = Sig.hasValue() ? *Sig : time(nullptr);
+
   return Buffer.commit();
 }