diff --git a/llvm/lib/CodeGen/WinEHPrepare.cpp b/llvm/lib/CodeGen/WinEHPrepare.cpp
--- a/llvm/lib/CodeGen/WinEHPrepare.cpp
+++ b/llvm/lib/CodeGen/WinEHPrepare.cpp
@@ -55,6 +55,12 @@
     "demote-catchswitch-only", cl::Hidden,
     cl::desc("Demote catchswitch BBs only (for wasm EH)"), cl::init(false));
 
+static cl::opt<bool> VerifyFuncletTokens(
+    "verify-funclet-tokens", cl::Hidden,
+    cl::desc("During WinEH preparations check for funclet tokens outside of "
+             "actual funclets"),
+    cl::init(false));
+
 namespace {
 
 class WinEHPrepare : public FunctionPass {
@@ -89,6 +95,7 @@
   void removeImplausibleInstructions(Function &F);
   void cleanupPreparedFunclets(Function &F);
   void verifyPreparedFunclets(Function &F);
+  void verifyNoFuncletTokens(const std::vector<BasicBlock *> &Blocks);
 
   bool DemoteCatchSwitchPHIOnly;
 
@@ -705,6 +712,13 @@
     for (BasicBlock *Color : Colors)
       FuncletBlocks[Color].push_back(&BB);
   }
+
+  if (VerifyFuncletTokens)
+    for (auto &Funclet : FuncletBlocks) {
+      auto *FuncletPad = dyn_cast<FuncletPadInst>(Funclet.first->getFirstNonPHI());
+      if (!FuncletPad)
+        verifyNoFuncletTokens(Funclet.second);
+    }
 }
 
 void WinEHPrepare::demotePHIsOnFunclets(Function &F,
@@ -1043,6 +1057,23 @@
 }
 #endif
 
+void WinEHPrepare::verifyNoFuncletTokens(const std::vector<BasicBlock *> &Blocks) {
+  for (BasicBlock *BB : Blocks) {
+    for (Instruction &I : *BB) {
+      if (auto *CB = dyn_cast<CallBase>(&I)) {
+        if (auto BU = CB->getOperandBundle(LLVMContext::OB_funclet)) {
+          std::string Buffer;
+          raw_string_ostream OS(Buffer);
+          OS << "Invalid funclet token in BasicBlock " << BB->getName();
+          Value *FuncletBundleOperand = BU->Inputs.front();
+          OS << " outside funclet:" << *FuncletBundleOperand << "\n";
+          report_fatal_error(OS.str().c_str());
+        }
+      }
+    }
+  }
+}
+
 bool WinEHPrepare::prepareExplicitEH(Function &F) {
   // Remove unreachable blocks.  It is not valuable to assign them a color and
   // their existence can trick us into thinking values are alive when they are
diff --git a/llvm/test/CodeGen/WinEH/wineh-funclet-bundle-validation.ll b/llvm/test/CodeGen/WinEH/wineh-funclet-bundle-validation.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/CodeGen/WinEH/wineh-funclet-bundle-validation.ll
@@ -0,0 +1,33 @@
+; RUN: not llc < %s -mtriple=x86_64-windows-msvc -verify-funclet-tokens -o - 2>&1 | FileCheck %s --check-prefix=CHECK-ERROR
+
+declare void @opaque()
+
+declare i32 @__CxxFrameHandler3(...)
+
+declare void @llvm.objc.storeStrong(ptr, ptr) #0
+
+define void @invalid_funclet_token() personality ptr @__CxxFrameHandler3 {
+entry:
+  invoke void @opaque()
+          to label %invoke.cont unwind label %catch.dispatch
+
+catch.dispatch:                                   ; preds = %entry
+  %0 = catchswitch within none [label %catch] unwind to caller
+
+invoke.cont:                                      ; preds = %entry
+  br label %eh.cont
+
+eh.cont:                                          ; preds = %catchret.dest, %invoke.cont
+  ret void
+
+catch:                                            ; preds = %catch.dispatch
+  %1 = catchpad within %0 [ptr null, i32 0, ptr null]
+  catchret from %1 to label %catchret.dest
+
+; CHECK-ERROR: LLVM ERROR: Invalid funclet token in BasicBlock catchret.dest outside funclet
+catchret.dest:                                    ; preds = %catch
+  call void @llvm.objc.storeStrong(ptr null, ptr null) [ "funclet"(token %1) ]
+  br label %eh.cont
+}
+
+attributes #0 = { nounwind }