Index: lld/trunk/COFF/InputFiles.cpp
===================================================================
--- lld/trunk/COFF/InputFiles.cpp
+++ lld/trunk/COFF/InputFiles.cpp
@@ -291,7 +291,8 @@
     } else {
       bool Replaceable = (SymbolDef == LTO_SYMBOL_DEFINITION_TENTATIVE ||
                           (Attrs & LTO_SYMBOL_COMDAT));
-      SymbolBodies.push_back(new (Alloc) DefinedBitcode(SymName, Replaceable));
+      SymbolBodies.push_back(new (Alloc) DefinedBitcode(this, SymName,
+                                                        Replaceable));
     }
   }
 
Index: lld/trunk/COFF/Symbols.h
===================================================================
--- lld/trunk/COFF/Symbols.h
+++ lld/trunk/COFF/Symbols.h
@@ -28,6 +28,7 @@
 using llvm::object::coff_symbol_generic;
 
 class ArchiveFile;
+class BitcodeFile;
 class InputFile;
 class ObjectFile;
 class SymbolBody;
@@ -334,15 +335,19 @@
 };
 
 class DefinedBitcode : public Defined {
+  friend SymbolBody;
 public:
-  DefinedBitcode(StringRef N, bool IsReplaceable)
-      : Defined(DefinedBitcodeKind, N) {
+  DefinedBitcode(BitcodeFile *F, StringRef N, bool IsReplaceable)
+      : Defined(DefinedBitcodeKind, N), File(F) {
     this->IsReplaceable = IsReplaceable;
   }
 
   static bool classof(const SymbolBody *S) {
     return S->kind() == DefinedBitcodeKind;
   }
+
+private:
+  BitcodeFile *File;
 };
 
 } // namespace coff
Index: lld/trunk/COFF/Symbols.cpp
===================================================================
--- lld/trunk/COFF/Symbols.cpp
+++ lld/trunk/COFF/Symbols.cpp
@@ -138,6 +138,9 @@
   if (auto *D = dyn_cast<DefinedCOFF>(this)) {
     N += " ";
     N += D->File->getShortName();
+  } else if (auto *D = dyn_cast<DefinedBitcode>(this)) {
+    N += " ";
+    N += D->File->getShortName();
   }
   return N;
 }
Index: lld/trunk/test/COFF/Inputs/conflict.ll
===================================================================
--- lld/trunk/test/COFF/Inputs/conflict.ll
+++ lld/trunk/test/COFF/Inputs/conflict.ll
@@ -0,0 +1,3 @@
+define void @foo() {
+  ret void
+}
Index: lld/trunk/test/COFF/conflict.test
===================================================================
--- lld/trunk/test/COFF/conflict.test
+++ lld/trunk/test/COFF/conflict.test
@@ -3,7 +3,12 @@
 # RUN: not lld -flavor link2 /out:%t.exe %t1.obj %t2.obj >& %t.log
 # RUN: FileCheck %s < %t.log
 
-# CHECK: duplicate symbol: foo {{.+}} and foo {{.+}}
+# RUN: llvm-as -o %t.lto1.obj %S/Inputs/conflict.ll
+# RUN: llvm-as -o %t.lto2.obj %S/Inputs/conflict.ll
+# RUN: not lld -flavor link2 /out:%t.exe %t.lto1.obj %t.lto2.obj >& %t.log
+# RUN: FileCheck %s < %t.log
+
+# CHECK: duplicate symbol: foo {{.+}}1.obj and foo {{.+}}2.obj
 
 ---
 header: