Index: llvm/trunk/lib/Object/RecordStreamer.h
===================================================================
--- llvm/trunk/lib/Object/RecordStreamer.h
+++ llvm/trunk/lib/Object/RecordStreamer.h
@@ -55,6 +55,15 @@
                     unsigned ByteAlignment, SMLoc Loc = SMLoc()) override;
   void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
                         unsigned ByteAlignment) override;
+
+  // Ignore COFF-specific directives; we do not need any information from them,
+  // but the default implementation of these methods crashes, so we override
+  // them with versions that do nothing.
+  void BeginCOFFSymbolDef(const MCSymbol *Symbol) override {}
+  void EmitCOFFSymbolStorageClass(int StorageClass) override {}
+  void EmitCOFFSymbolType(int Type) override {}
+  void EndCOFFSymbolDef() override {}
+
   /// Record .symver aliases for later processing.
   void emitELFSymverDirective(StringRef AliasName,
                               const MCSymbol *Aliasee) override;
Index: llvm/trunk/test/MC/COFF/module-asm-coff.ll
===================================================================
--- llvm/trunk/test/MC/COFF/module-asm-coff.ll
+++ llvm/trunk/test/MC/COFF/module-asm-coff.ll
@@ -0,0 +1,21 @@
+; Tests COFF-specific directives in module level assembly.
+
+; RUN: llc -filetype=obj %s -o %t.obj
+; RUN: llvm-readobj -t %t.obj | FileCheck %s
+; RUN: opt -thinlto-bc %s -o %t.thinlto.bc
+; RUN: llvm-lto2 run %t.thinlto.bc -o %t.thinlto.obj -r=%t.thinlto.bc,foo,plx
+; RUN: llvm-readobj -t %t.thinlto.obj.1 | FileCheck %s
+
+target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-pc-windows-msvc19.0.24210"
+
+module asm ".text"
+module asm ".def foo; .scl 3; .type 32; .endef"
+module asm ".global foo"
+module asm "foo:"
+module asm "  ret"
+
+; CHECK: Symbol {
+; CHECK:   Name: foo
+; CHECK:   StorageClass:
+; CHECK-SAME: Static (0x3)