Index: clang/lib/AST/Interp/EvalEmitter.h
===================================================================
--- clang/lib/AST/Interp/EvalEmitter.h
+++ clang/lib/AST/Interp/EvalEmitter.h
@@ -92,6 +92,8 @@
   /// Temporaries which require storage.
   llvm::DenseMap<unsigned, std::unique_ptr<char[]>> Locals;
 
+  InlineDescriptor *localInlineDesc(unsigned LocalIndex);
+
   // The emitter always tracks the current instruction and sets OpPC to a token
   // value which is mapped to the location of the opcode being evaluated.
   CodePtr OpPC;
Index: clang/lib/AST/Interp/EvalEmitter.cpp
===================================================================
--- clang/lib/AST/Interp/EvalEmitter.cpp
+++ clang/lib/AST/Interp/EvalEmitter.cpp
@@ -49,25 +49,33 @@
 
 EvalEmitter::LabelTy EvalEmitter::getLabel() { return NextLabel++; }
 
+InlineDescriptor *EvalEmitter::localInlineDesc(unsigned LocalIndex) {
+  auto It = Locals.find(LocalIndex);
+  assert(It != Locals.end() && "Missing local variable");
+  Block *B = reinterpret_cast<Block *>(It->second.get());
+  return reinterpret_cast<InlineDescriptor *>(B->rawData());
+}
+
 Scope::Local EvalEmitter::createLocal(Descriptor *D) {
   // Allocate memory for a local.
   auto Memory = std::make_unique<char[]>(sizeof(Block) + D->getAllocSize());
   auto *B = new (Memory.get()) Block(D, /*isStatic=*/false);
   B->invokeCtor();
 
-  // Initialize local variable inline descriptor.
-  InlineDescriptor &Desc = *reinterpret_cast<InlineDescriptor *>(B->rawData());
-  Desc.Desc = D;
-  Desc.Offset = sizeof(InlineDescriptor);
-  Desc.IsActive = true;
-  Desc.IsBase = false;
-  Desc.IsMutable = false;
-  Desc.IsConst = false;
-  Desc.IsInitialized = false;
-
   // Register the local.
   unsigned Off = Locals.size();
   Locals.insert({Off, std::move(Memory)});
+
+  // Initialize local variable inline descriptor.
+  InlineDescriptor *Desc = localInlineDesc(Off);
+  Desc->Desc = D;
+  Desc->Offset = sizeof(InlineDescriptor);
+  Desc->IsActive = true;
+  Desc->IsBase = false;
+  Desc->IsMutable = false;
+  Desc->IsConst = false;
+  Desc->IsInitialized = false;
+
   return {Off, D};
 }
 
@@ -240,8 +248,8 @@
   assert(It != Locals.end() && "Missing local variable");
   auto *B = reinterpret_cast<Block *>(It->second.get());
   *reinterpret_cast<T *>(B->data()) = S.Stk.pop<T>();
-  InlineDescriptor &Desc = *reinterpret_cast<InlineDescriptor *>(B->rawData());
-  Desc.IsInitialized = true;
+  InlineDescriptor *Desc = localInlineDesc(I);
+  Desc->IsInitialized = true;
 
   return true;
 }
@@ -254,6 +262,10 @@
     auto It = Locals.find(Local.Offset);
     assert(It != Locals.end() && "Missing local variable");
     S.deallocate(reinterpret_cast<Block *>(It->second.get()));
+    // Just make sure we're runnnig into some kind of error when a
+    // local variable is used after being destroyed.
+    InlineDescriptor *ID = localInlineDesc(I);
+    std::memset(ID, 0, sizeof(InlineDescriptor));
   }
 
   return true;
Index: clang/lib/AST/Interp/InterpFrame.cpp
===================================================================
--- clang/lib/AST/Interp/InterpFrame.cpp
+++ clang/lib/AST/Interp/InterpFrame.cpp
@@ -75,6 +75,10 @@
 void InterpFrame::destroy(unsigned Idx) {
   for (auto &Local : Func->getScope(Idx).locals()) {
     S.deallocate(reinterpret_cast<Block *>(localBlock(Local.Offset)));
+    // Just make sure we're runnnig into some kind of error when a
+    // local variable is used after being destroyed.
+    InlineDescriptor *ID = localInlineDesc(Local.Offset);
+    std::memset(ID, 0, sizeof(InlineDescriptor));
   }
 }