Index: COFF/InputFiles.cpp
===================================================================
--- COFF/InputFiles.cpp
+++ COFF/InputFiles.cpp
@@ -340,7 +340,7 @@
 
 void BitcodeFile::parse() {
   Obj = check(lto::InputFile::create(
-      MemoryBufferRef(MB.getBuffer(), Saver.save(MB.getBufferIdentifier()))));
+      MemoryBufferRef(MB.getBuffer(), Saver.save(ParentName + MB.getBufferIdentifier()))));
   for (const lto::InputFile::Symbol &ObjSym : Obj->symbols()) {
     StringRef SymName = Saver.save(ObjSym.getName());
     auto Flags = ObjSym.getFlags();