Index: llvm/trunk/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
===================================================================
--- llvm/trunk/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
+++ llvm/trunk/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -1350,7 +1350,10 @@
 MCSection *TargetLoweringObjectFileCOFF::getSectionForConstant(
     const DataLayout &DL, SectionKind Kind, const Constant *C,
     unsigned &Align) const {
-  if (Kind.isMergeableConst() && C) {
+  if (Kind.isMergeableConst() && C &&
+      getContext().getAsmInfo()->hasCOFFAssociativeComdats()) {
+    // GNU binutils doesn't support the kind of symbol with a null
+    // storage class that this generates.
     const unsigned Characteristics = COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
                                      COFF::IMAGE_SCN_MEM_READ |
                                      COFF::IMAGE_SCN_LNK_COMDAT;
Index: llvm/trunk/test/CodeGen/X86/win_cst_pool.ll
===================================================================
--- llvm/trunk/test/CodeGen/X86/win_cst_pool.ll
+++ llvm/trunk/test/CodeGen/X86/win_cst_pool.ll
@@ -1,4 +1,5 @@
 ; RUN: llc < %s -mtriple=x86_64-win32 -mattr=sse2 -mattr=avx | FileCheck %s
+; RUN: llc < %s -mtriple=x86_64-win32-gnu -mattr=sse2 -mattr=avx | FileCheck -check-prefix=MINGW %s
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-pc-windows-msvc"
 
@@ -14,6 +15,14 @@
 ; CHECK:               movsd   __real@0000000000800000(%rip), %xmm0
 ; CHECK-NEXT:          ret
 
+; MINGW:              .section        .rdata,"dr"
+; MINGW-NEXT:         .p2align  3
+; MINGW-NEXT: [[LABEL:\.LC.*]]:
+; MINGW-NEXT:         .quad   8388608
+; MINGW:      double:
+; MINGW:               movsd   [[LABEL]](%rip), %xmm0
+; MINGW-NEXT:          ret
+
 define <4 x i32> @vec1() {
   ret <4 x i32> <i32 3, i32 2, i32 1, i32 0>
 }