Fix .comm and .lcomm on COFF.

These should not use COMDATs. GNU as uses .bss for .lcomm and section 0 for
.comm.

Given

static int a;
int b;

MSVC puts both in .bss. This patch then puts both .comm and .lcomm on .bss. With
this change we agree with gas on .lcomm, are much closer on .comm and clang-cl
matches msvc on the above example.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195654 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 2 insertions, 18 deletions

diff --git a/lib/MC/WinCOFFStreamer.cpp b/lib/MC/WinCOFFStreamer.cpp
index 0c205e5070..af313b2ff8 100644
--- a/lib/MC/WinCOFFStreamer.cpp
+++ b/lib/MC/WinCOFFStreamer.cpp
@@ -140,28 +140,12 @@ void WinCOFFStreamer::AddCommonSymbol(MCSymbol *Symbol, uint64_t Size,
                                       unsigned ByteAlignment, bool External) {
   assert(!Symbol->isInSection() && "Symbol must not already have a section!");
 
-  std::string SectionName(".bss$linkonce");
-  SectionName.append(Symbol->getName().begin(), Symbol->getName().end());
-
-  MCSymbolData &SymbolData = getAssembler().getOrCreateSymbolData(*Symbol);
-
-  unsigned Characteristics =
-    COFF::IMAGE_SCN_LNK_COMDAT |
-    COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA |
-    COFF::IMAGE_SCN_MEM_READ |
-    COFF::IMAGE_SCN_MEM_WRITE;
-
-  int Selection = COFF::IMAGE_COMDAT_SELECT_LARGEST;
-
-  const MCSection *Section = MCStreamer::getContext().getCOFFSection(
-      SectionName, Characteristics, SectionKind::getBSS(), Symbol->getName(),
-      Selection);
-
+  const MCSectionCOFF *Section = getSectionBSS();
   MCSectionData &SectionData = getAssembler().getOrCreateSectionData(*Section);
-
   if (SectionData.getAlignment() < ByteAlignment)
     SectionData.setAlignment(ByteAlignment);
 
+  MCSymbolData &SymbolData = getAssembler().getOrCreateSymbolData(*Symbol);
   SymbolData.setExternal(External);
 
   AssignSection(Symbol, Section);