2 files changed, 14 insertions, 5 deletions
diff --git a/clang/lib/CodeGen/CGDecl.cpp b/clang/lib/CodeGen/CGDecl.cpp
index b52ea9da301..4230dbdf293 100644
--- a/clang/lib/CodeGen/CGDecl.cpp
+++ b/clang/lib/CodeGen/CGDecl.cpp
@@ -1066,6 +1066,7 @@ void CodeGenFunction::EmitAndRegisterVariableArrayDimensions(
   // For each dimension stores its QualType and corresponding
   // size-expression Value.
   SmallVector<CodeGenFunction::VlaSizePair, 4> Dimensions;
+  SmallVector<IdentifierInfo *, 4> VLAExprNames;
 
   // Break down the array into individual dimensions.
   QualType Type1D = D.getType();
@@ -1074,8 +1075,14 @@ void CodeGenFunction::EmitAndRegisterVariableArrayDimensions(
     if (auto *C = dyn_cast<llvm::ConstantInt>(VlaSize.NumElts))
       Dimensions.emplace_back(C, Type1D.getUnqualifiedType());
     else {
-      auto SizeExprAddr = CreateDefaultAlignTempAlloca(
-          VlaSize.NumElts->getType(), "__vla_expr");
+      // Generate a locally unique name for the size expression.
+      Twine Name = Twine("__vla_expr") + Twine(VLAExprCounter++);
+      SmallString<12> Buffer;
+      StringRef NameRef = Name.toStringRef(Buffer);
+      auto &Ident = getContext().Idents.getOwn(NameRef);
+      VLAExprNames.push_back(&Ident);
+      auto SizeExprAddr =
+          CreateDefaultAlignTempAlloca(VlaSize.NumElts->getType(), NameRef);
       Builder.CreateStore(VlaSize.NumElts, SizeExprAddr);
       Dimensions.emplace_back(SizeExprAddr.getPointer(),
                               Type1D.getUnqualifiedType());
@@ -1089,20 +1096,20 @@ void CodeGenFunction::EmitAndRegisterVariableArrayDimensions(
   // Register each dimension's size-expression with a DILocalVariable,
   // so that it can be used by CGDebugInfo when instantiating a DISubrange
   // to describe this array.
+  unsigned NameIdx = 0;
   for (auto &VlaSize : Dimensions) {
     llvm::Metadata *MD;
     if (auto *C = dyn_cast<llvm::ConstantInt>(VlaSize.NumElts))
       MD = llvm::ConstantAsMetadata::get(C);
     else {
       // Create an artificial VarDecl to generate debug info for.
-      IdentifierInfo &NameIdent = getContext().Idents.getOwn(
-          cast<llvm::AllocaInst>(VlaSize.NumElts)->getName());
+      IdentifierInfo *NameIdent = VLAExprNames[NameIdx++];
       auto VlaExprTy = VlaSize.NumElts->getType()->getPointerElementType();
       auto QT = getContext().getIntTypeForBitwidth(
           VlaExprTy->getScalarSizeInBits(), false);
       auto *ArtificialDecl = VarDecl::Create(
           getContext(), const_cast<DeclContext *>(D.getDeclContext()),
-          D.getLocation(), D.getLocation(), &NameIdent, QT,
+          D.getLocation(), D.getLocation(), NameIdent, QT,
           getContext().CreateTypeSourceInfo(QT), SC_Auto);
       ArtificialDecl->setImplicit();
 
diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index f6b76294ae0..9f09119ee1f 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -1197,6 +1197,8 @@ public:
 
 private:
   CGDebugInfo *DebugInfo;
+  /// Used to create unique names for artificial VLA size debug info variables.
+  unsigned VLAExprCounter = 0;
   bool DisableDebugInfo = false;
 
   /// DidCallStackSave - Whether llvm.stacksave has been called. Used to avoid