Index: include/llvm/ExecutionEngine/Orc/OrcRemoteTargetClient.h
===================================================================
--- include/llvm/ExecutionEngine/Orc/OrcRemoteTargetClient.h
+++ include/llvm/ExecutionEngine/Orc/OrcRemoteTargetClient.h
@@ -168,10 +168,8 @@
 
     void deregisterEHFrames() override {
       for (auto &Frame : RegisteredEHFrames) {
-        auto Err = Client.deregisterEHFrames(Frame.Addr, Frame.Size);
         // FIXME: Add error poll.
-        assert(!Err && "Failed to register remote EH frames.");
-        (void)Err;
+        llvm::cantFail(Client.deregisterEHFrames(Frame.Addr, Frame.Size));
       }
     }
 
Index: unittests/Support/ErrorTest.cpp
===================================================================
--- unittests/Support/ErrorTest.cpp
+++ unittests/Support/ErrorTest.cpp
@@ -482,7 +482,7 @@
 }
 
 // Test that cantFail results in a crash if you pass it a failure value.
-#if LLVM_ENABLE_ABI_BREAKING_CHECKS
+#if LLVM_ENABLE_ABI_BREAKING_CHECKS && !defined(NDEBUG)
 TEST(Error, CantFailDeath) {
   EXPECT_DEATH(
       cantFail(make_error<StringError>("foo", inconvertibleErrorCode())),