Revert Don't create new comdats in CodeGen

It breaks AddressSanitizer on Windows.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226173 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 14 insertions, 5 deletions

diff --git a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
index b9a3ad23d1f..9f1e06b4725 100644
--- a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
+++ b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -257,7 +257,8 @@ SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
 
   // If this global is linkonce/weak and the target handles this by emitting it
   // into a 'uniqued' section name, create and return the section now.
-  if ((EmitUniquedSection && !Kind.isCommon()) || GV->hasComdat()) {
+  if ((GV->isWeakForLinker() || EmitUniquedSection || GV->hasComdat()) &&
+      !Kind.isCommon()) {
     StringRef Prefix = getSectionPrefixForGlobal(Kind);
 
     SmallString<128> Name(Prefix);
@@ -265,9 +266,12 @@ SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
 
     StringRef Group = "";
     unsigned Flags = getELFSectionFlags(Kind);
-    if (const Comdat *C = getELFComdat(GV)) {
+    if (GV->isWeakForLinker() || GV->hasComdat()) {
+      if (const Comdat *C = getELFComdat(GV))
+        Group = C->getName();
+      else
+        Group = Name.substr(Prefix.size());
       Flags |= ELF::SHF_GROUP;
-      Group = C->getName();
     }
 
     return getContext().getELFSection(Name.str(),
@@ -797,7 +801,7 @@ const MCSection *TargetLoweringObjectFileCOFF::getExplicitSectionGlobal(
   unsigned Characteristics = getCOFFSectionFlags(Kind);
   StringRef Name = GV->getSection();
   StringRef COMDATSymName = "";
-  if (GV->hasComdat()) {
+  if ((GV->isWeakForLinker() || GV->hasComdat()) && !Kind.isCommon()) {
     Selection = getSelectionForCOFF(GV);
     const GlobalValue *ComdatGV;
     if (Selection == COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE)
@@ -844,7 +848,12 @@ SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
   else
     EmitUniquedSection = TM.getDataSections();
 
-  if ((EmitUniquedSection && !Kind.isCommon()) || GV->hasComdat()) {
+  // If this global is linkonce/weak and the target handles this by emitting it
+  // into a 'uniqued' section name, create and return the section now.
+  // Section names depend on the name of the symbol which is not feasible if the
+  // symbol has private linkage.
+  if ((GV->isWeakForLinker() || EmitUniquedSection || GV->hasComdat()) &&
+      !Kind.isCommon()) {
     const char *Name = getCOFFSectionNameForUniqueGlobal(Kind);
     unsigned Characteristics = getCOFFSectionFlags(Kind);