Index: llvm/include/llvm/Support/Error.h
===================================================================
--- llvm/include/llvm/Support/Error.h
+++ llvm/include/llvm/Support/Error.h
@@ -670,7 +670,7 @@
   }
 #endif
 
-  void assertIsChecked() {
+  void assertIsChecked() const {
 #if LLVM_ENABLE_ABI_BREAKING_CHECKS
     if (LLVM_UNLIKELY(Unchecked))
       fatalUncheckedExpected();
Index: llvm/unittests/Support/ErrorTest.cpp
===================================================================
--- llvm/unittests/Support/ErrorTest.cpp
+++ llvm/unittests/Support/ErrorTest.cpp
@@ -565,7 +565,7 @@
 // Test runs in debug mode only.
 #if LLVM_ENABLE_ABI_BREAKING_CHECKS
 TEST(Error, UncheckedExpectedInSuccessModeAccess) {
-  EXPECT_DEATH({ Expected<int> A = 7; *A; },
+  EXPECT_DEATH({ const Expected<int> A = 7; *A; },
                "Expected<T> must be checked before access or destruction.")
     << "Unchecekd Expected<T> success value did not cause an abort().";
 }