diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index b3974b6..7fa4fdd 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -715,6 +715,63 @@
     GV->setVisibility(GetLLVMVisibility(LV.getVisibility()));
 }
 
+static bool shouldAssumeDSOLocal(const CodeGenModule &CGM,
+                                 llvm::GlobalValue *GV, const NamedDecl *D) {
+  const llvm::Triple &TT = CGM.getTriple();
+  // Only handle ELF for now.
+  if (!TT.isOSBinFormatELF())
+    return false;
+
+  // If this is not an executable, don't assume anything is local.
+  const auto &CGOpts = CGM.getCodeGenOpts();
+  llvm::Reloc::Model RM = CGOpts.RelocationModel;
+  const auto &LOpts = CGM.getLangOpts();
+  if (RM != llvm::Reloc::Static && !LOpts.PIE)
+    return false;
+
+  // A definition cannot be preempted from an executable.
+  if (!GV->isDeclarationForLinker())
+    return true;
+
+  // Most PIC code sequences that assume that a symbol is local cannot produce a
+  // 0 if it turns out the symbol is undefined. While this is ABI and relocation
+  // depended, it seems worth it to handle it here.
+  if (RM == llvm::Reloc::PIC_ && GV->hasExternalWeakLinkage())
+    return false;
+
+  // PPC has no copy relocations and cannot use a plt entry as a symbol address.
+  llvm::Triple::ArchType Arch = TT.getArch();
+  if (Arch == llvm::Triple::ppc || Arch == llvm::Triple::ppc64 ||
+      Arch == llvm::Triple::ppc64le)
+    return false;
+
+  // If we can use copy relocations we can assume it is local.
+  if (isa<VarDecl>(D) &&
+      (RM == llvm::Reloc::Static || CGOpts.PIECopyRelocations))
+    return true;
+
+  // If we can use a plt entry as the symbol address we can assume it
+  // is local.
+  // FIXME: This should work for PIE, but the gold linker doesn't support it.
+  if (isa<FunctionDecl>(D) && !CGOpts.NoPLT && RM == llvm::Reloc::Static)
+    return true;
+
+  // Otherwise don't assue it is local.
+  return false;
+}
+
+void CodeGenModule::setDSOLocal(llvm::GlobalValue *GV,
+                                const NamedDecl *D) const {
+  if (shouldAssumeDSOLocal(*this, GV, D))
+    GV->setDSOLocal(true);
+}
+
+void CodeGenModule::setGVProperties(llvm::GlobalValue *GV,
+                                    const NamedDecl *D) const {
+  setGlobalVisibility(GV, D);
+  setDSOLocal(GV, D);
+}
+
 static llvm::GlobalVariable::ThreadLocalMode GetLLVMTLSModel(StringRef S) {
   return llvm::StringSwitch<llvm::GlobalVariable::ThreadLocalMode>(S)
       .Case("global-dynamic", llvm::GlobalVariable::GeneralDynamicTLSModel)
@@ -1172,7 +1229,7 @@
 void CodeGenModule::SetCommonAttributes(const Decl *D,
                                         llvm::GlobalValue *GV) {
   if (const auto *ND = dyn_cast_or_null<NamedDecl>(D))
-    setGlobalVisibility(GV, ND);
+    setGVProperties(GV, ND);
   else
     GV->setVisibility(llvm::GlobalValue::DefaultVisibility);
 
@@ -1312,7 +1369,7 @@
   // overridden by a definition.
 
   setLinkageForGV(F, FD);
-  setGlobalVisibility(F, FD);
+  setGVProperties(F, FD);
 
   if (FD->getAttr<PragmaClangTextSectionAttr>()) {
     F->addFnAttr("implicit-section-name");
@@ -2639,7 +2696,7 @@
     GV->setAlignment(getContext().getDeclAlign(D).getQuantity());
 
     setLinkageForGV(GV, D);
-    setGlobalVisibility(GV, D);
+    setGVProperties(GV, D);
 
     if (D->getTLSKind()) {
       if (D->getTLSKind() == VarDecl::TLS_Dynamic)
@@ -3458,7 +3515,7 @@
   setFunctionDLLStorageClass(GD, Fn);
 
   // FIXME: this is redundant with part of setFunctionDefinitionAttributes
-  setGlobalVisibility(Fn, D);
+  setGVProperties(Fn, D);
 
   MaybeHandleStaticInExternC(D, Fn);
 
@@ -4054,7 +4111,7 @@
       getModule(), Type, Constant, Linkage, InitialValue, Name.c_str(),
       /*InsertBefore=*/nullptr, llvm::GlobalVariable::NotThreadLocal, TargetAS);
   if (emitter) emitter->finalize(GV);
-  setGlobalVisibility(GV, VD);
+  setGVProperties(GV, VD);
   GV->setAlignment(Align.getQuantity());
   if (supportsCOMDAT() && GV->isWeakForLinker())
     GV->setComdat(TheModule.getOrInsertComdat(GV->getName()));