Merge pull request #441 from sandstorm-io/fix-no-exceptions

Fix build with -fno-exceptions

c++/src/capnp/compat/json-test.c++

@@ -198,42 +198,48 @@ KJ_TEST("decode all types") {
     auto root = message.initRoot<TestAllTypes>(); \
     KJ_EXPECT_THROW_MESSAGE(errorMessage, json.decode(s, root)); \
   }
+#define CASE_THROW_RECOVERABLE(s, errorMessage) \
+  { \
+    MallocMessageBuilder message; \
+    auto root = message.initRoot<TestAllTypes>(); \
+    KJ_EXPECT_THROW_RECOVERABLE_MESSAGE(errorMessage, json.decode(s, root)); \
+  }
 
   CASE(R"({})", root.getBoolField() == false);
   CASE(R"({"unknownField":7})", root.getBoolField() == false);
   CASE(R"({"boolField":true})", root.getBoolField() == true);
   CASE(R"({"int8Field":-128})", root.getInt8Field() == -128);
   CASE(R"({"int8Field":"127"})", root.getInt8Field() == 127);
-  CASE_THROW(R"({"int8Field":"-129"})", "Value out-of-range");
-  CASE_THROW(R"({"int8Field":128})", "Value out-of-range");
+  CASE_THROW_RECOVERABLE(R"({"int8Field":"-129"})", "Value out-of-range");
+  CASE_THROW_RECOVERABLE(R"({"int8Field":128})", "Value out-of-range");
   CASE(R"({"int16Field":-32768})", root.getInt16Field() == -32768);
   CASE(R"({"int16Field":"32767"})", root.getInt16Field() == 32767);
-  CASE_THROW(R"({"int16Field":"-32769"})", "Value out-of-range");
-  CASE_THROW(R"({"int16Field":32768})", "Value out-of-range");
+  CASE_THROW_RECOVERABLE(R"({"int16Field":"-32769"})", "Value out-of-range");
+  CASE_THROW_RECOVERABLE(R"({"int16Field":32768})", "Value out-of-range");
   CASE(R"({"int32Field":-2147483648})", root.getInt32Field() == -2147483648);
   CASE(R"({"int32Field":"2147483647"})", root.getInt32Field() == 2147483647);
   CASE(R"({"int64Field":-9007199254740992})", root.getInt64Field() == -9007199254740992LL);
   CASE(R"({"int64Field":9007199254740991})", root.getInt64Field() == 9007199254740991LL);
   CASE(R"({"int64Field":"-9223372036854775808"})", root.getInt64Field() == -9223372036854775808ULL);
   CASE(R"({"int64Field":"9223372036854775807"})", root.getInt64Field() == 9223372036854775807LL);
-  CASE_THROW(R"({"int64Field":"-9223372036854775809"})", "Value out-of-range");
-  CASE_THROW(R"({"int64Field":"9223372036854775808"})", "Value out-of-range");
+  CASE_THROW_RECOVERABLE(R"({"int64Field":"-9223372036854775809"})", "Value out-of-range");
+  CASE_THROW_RECOVERABLE(R"({"int64Field":"9223372036854775808"})", "Value out-of-range");
   CASE(R"({"uInt8Field":255})", root.getUInt8Field() == 255);
   CASE(R"({"uInt8Field":"0"})", root.getUInt8Field() == 0);
-  CASE_THROW(R"({"uInt8Field":"256"})", "Value out-of-range");
-  CASE_THROW(R"({"uInt8Field":-1})", "Value out-of-range");
+  CASE_THROW_RECOVERABLE(R"({"uInt8Field":"256"})", "Value out-of-range");
+  CASE_THROW_RECOVERABLE(R"({"uInt8Field":-1})", "Value out-of-range");
   CASE(R"({"uInt16Field":65535})", root.getUInt16Field() == 65535);
   CASE(R"({"uInt16Field":"0"})", root.getUInt16Field() == 0);
-  CASE_THROW(R"({"uInt16Field":"655356"})", "Value out-of-range");
-  CASE_THROW(R"({"uInt16Field":-1})", "Value out-of-range");
+  CASE_THROW_RECOVERABLE(R"({"uInt16Field":"655356"})", "Value out-of-range");
+  CASE_THROW_RECOVERABLE(R"({"uInt16Field":-1})", "Value out-of-range");
   CASE(R"({"uInt32Field":4294967295})", root.getUInt32Field() == 4294967295);
   CASE(R"({"uInt32Field":"0"})", root.getUInt32Field() == 0);
-  CASE_THROW(R"({"uInt32Field":"42949672956"})", "Value out-of-range");
-  CASE_THROW(R"({"uInt32Field":-1})", "Value out-of-range");
+  CASE_THROW_RECOVERABLE(R"({"uInt32Field":"42949672956"})", "Value out-of-range");
+  CASE_THROW_RECOVERABLE(R"({"uInt32Field":-1})", "Value out-of-range");
   CASE(R"({"uInt64Field":9007199254740991})", root.getUInt64Field() == 9007199254740991ULL);
   CASE(R"({"uInt64Field":"18446744073709551615"})", root.getUInt64Field() == 18446744073709551615ULL);
   CASE(R"({"uInt64Field":"0"})", root.getUInt64Field() == 0);
-  CASE_THROW(R"({"uInt64Field":"18446744073709551616"})", "Value out-of-range");
+  CASE_THROW_RECOVERABLE(R"({"uInt64Field":"18446744073709551616"})", "Value out-of-range");
   CASE(R"({"float32Field":0})", root.getFloat32Field() == 0);
   CASE(R"({"float32Field":4.5})", root.getFloat32Field() == 4.5);
   CASE(R"({"float32Field":null})", kj::isNaN(root.getFloat32Field()));
@@ -258,9 +264,9 @@ KJ_TEST("decode all types") {
   CASE(R"({"structField":{"boolField":true}})", root.getStructField().getBoolField() == true);
   CASE(R"({"enumField":"bar"})", root.getEnumField() == TestEnum::BAR);
 
-  CASE_THROW(R"({"int64Field":"177a"})", "String does not contain valid");
-  CASE_THROW(R"({"uInt64Field":"177a"})", "String does not contain valid");
-  CASE_THROW(R"({"float64Field":"177a"})", "String does not contain valid");
+  CASE_THROW_RECOVERABLE(R"({"int64Field":"177a"})", "String does not contain valid");
+  CASE_THROW_RECOVERABLE(R"({"uInt64Field":"177a"})", "String does not contain valid");
+  CASE_THROW_RECOVERABLE(R"({"float64Field":"177a"})", "String does not contain valid");
 
   CASE(R"({})", root.hasBoolList() == false);
   CASE(R"({"boolList":null})", root.hasBoolList() == false);
@@ -309,6 +315,7 @@ KJ_TEST("decode all types") {
   CASE(R"({"enumList":["bar"]})", root.getEnumList()[0] == TestEnum::BAR);
 #undef CASE
 #undef CASE_THROW
+#undef CASE_THROW_RECOVERABLE
 }
 
 KJ_TEST("decode test message") {

c++/src/capnp/fuzz-test.c++

@@ -107,19 +107,19 @@ void traverseCatchingExceptions(kj::ArrayPtr<const word> data) {
   // Try traversing through Checker.
   kj::runCatchingExceptions([&]() {
     FlatArrayMessageReader reader(data);
-    KJ_ASSERT(Checker::check(reader) != 0);
+    KJ_ASSERT(Checker::check(reader) != 0) { break; }
   });
 
   // Try traversing through AnyPointer.
   kj::runCatchingExceptions([&]() {
     FlatArrayMessageReader reader(data);
-    KJ_ASSERT(traverse(reader.getRoot<AnyPointer>()) != 0);
+    KJ_ASSERT(traverse(reader.getRoot<AnyPointer>()) != 0) { break; }
   });
 
   // Try counting the size..
   kj::runCatchingExceptions([&]() {
     FlatArrayMessageReader reader(data);
-    KJ_ASSERT(reader.getRoot<AnyPointer>().targetSize().wordCount != 0);
+    KJ_ASSERT(reader.getRoot<AnyPointer>().targetSize().wordCount != 0) { break; }
   });
 
   // Try copying into a builder, and if that works, traversing it with Checker.
@@ -128,7 +128,7 @@ void traverseCatchingExceptions(kj::ArrayPtr<const word> data) {
     FlatArrayMessageReader reader(data);
     MallocMessageBuilder copyBuilder(buffer);
     copyBuilder.setRoot(reader.getRoot<AnyPointer>());
-    KJ_ASSERT(Checker::check(copyBuilder) != 0);
+    KJ_ASSERT(Checker::check(copyBuilder) != 0) { break; }
   });
 }
 

c++/src/capnp/layout.c++

@@ -555,11 +555,17 @@ struct WireHelpers {
       // object.
       ref = pad + 1;
 
-      segment = segment->getArena()->tryGetSegment(pad->farRef.segmentId.get());
-      KJ_REQUIRE(segment != nullptr, "Message contains double-far pointer to unknown segment.") {
+      SegmentReader* newSegment = segment->getArena()->tryGetSegment(pad->farRef.segmentId.get());
+      KJ_REQUIRE(newSegment != nullptr,
+          "Message contains double-far pointer to unknown segment.") {
+        return nullptr;
+      }
+      KJ_REQUIRE(pad->kind() == WirePointer::FAR,
+          "Second word of double-far pad must be far pointer.") {
         return nullptr;
       }
 
+      segment = newSegment;
       return segment->getStartPtr() + pad->farPositionInSegment();
     } else {
       return refTarget;
@@ -1611,20 +1617,30 @@ struct WireHelpers {
       }
     } else {
       word* ptr = followFars(ref, refTarget, segment);
-      char* cptr = reinterpret_cast<char*>(ptr);
+      byte* bptr = reinterpret_cast<byte*>(ptr);
 
       KJ_REQUIRE(ref->kind() == WirePointer::LIST,
-          "Called getText{Field,Element}() but existing pointer is not a list.");
+          "Called getText{Field,Element}() but existing pointer is not a list.") {
+        goto useDefault;
+      }
       KJ_REQUIRE(ref->listRef.elementSize() == ElementSize::BYTE,
-          "Called getText{Field,Element}() but existing list pointer is not byte-sized.");
-
-      size_t size = unbound(subtractChecked(ref->listRef.elementCount() / ELEMENTS, ONE,
-          []() { KJ_FAIL_REQUIRE("zero-size blob can't be text (need NUL terminator)"); }));
-      KJ_REQUIRE(cptr[size] == '\0', "Text blob missing NUL terminator.") {
+          "Called getText{Field,Element}() but existing list pointer is not byte-sized.") {
         goto useDefault;
       }
 
-      return Text::Builder(cptr, size);
+      auto maybeSize = trySubtract(ref->listRef.elementCount() * (ONE * BYTES / ELEMENTS),
+                                   ONE * BYTES);
+      KJ_IF_MAYBE(size, maybeSize) {
+        KJ_REQUIRE(*(bptr + *size) == '\0', "Text blob missing NUL terminator.") {
+          goto useDefault;
+        }
+
+        return Text::Builder(reinterpret_cast<char*>(bptr), unbound(*size / BYTES));
+      } else {
+        KJ_FAIL_REQUIRE("zero-size blob can't be text (need NUL terminator)") {
+          goto useDefault;
+        };
+      }
     }
   }
 
@@ -1663,6 +1679,7 @@ struct WireHelpers {
       WirePointer* ref, word* refTarget, SegmentBuilder* segment, CapTableBuilder* capTable,
       const void* defaultValue, BlobSize defaultSize)) {
     if (ref->isNull()) {
+    useDefault:
       if (defaultSize == ZERO * BYTES) {
         return nullptr;
       } else {
@@ -1674,9 +1691,13 @@ struct WireHelpers {
       word* ptr = followFars(ref, refTarget, segment);
 
       KJ_REQUIRE(ref->kind() == WirePointer::LIST,
-          "Called getData{Field,Element}() but existing pointer is not a list.");
+          "Called getData{Field,Element}() but existing pointer is not a list.") {
+        goto useDefault;
+      }
       KJ_REQUIRE(ref->listRef.elementSize() == ElementSize::BYTE,
-          "Called getData{Field,Element}() but existing list pointer is not byte-sized.");
+          "Called getData{Field,Element}() but existing list pointer is not byte-sized.") {
+        goto useDefault;
+      }
 
       return Data::Builder(reinterpret_cast<byte*>(ptr),
           unbound(ref->listRef.elementCount() / ELEMENTS));
@@ -2653,13 +2674,13 @@ PointerType PointerReader::getPointerType() const {
     WireHelpers::followFars(ptr, refTarget, sgmt);
     switch(ptr->kind()) {
       case WirePointer::FAR:
-        KJ_FAIL_ASSERT("far pointer not followed?");
+        KJ_FAIL_ASSERT("far pointer not followed?") { return PointerType::NULL_; }
       case WirePointer::STRUCT:
         return PointerType::STRUCT;
       case WirePointer::LIST:
         return PointerType::LIST;
       case WirePointer::OTHER:
-        KJ_REQUIRE(ptr->isCapability(), "unknown pointer type");
+        KJ_REQUIRE(ptr->isCapability(), "unknown pointer type") { return PointerType::NULL_; }
         return PointerType::CAPABILITY;
     }
     KJ_UNREACHABLE;

c++/src/capnp/layout.h

@@ -104,7 +104,9 @@ inline KJ_CONSTEXPR() BitsPerElementTableType dataBitsPerElement(ElementSize siz
 }
 
 inline constexpr PointersPerElementN<1> pointersPerElement(ElementSize size) {
-  return size == ElementSize::POINTER ? ONE * POINTERS / ELEMENTS : ZERO * POINTERS / ELEMENTS;
+  return size == ElementSize::POINTER
+      ? PointersPerElementN<1>(ONE * POINTERS / ELEMENTS)
+      : PointersPerElementN<1>(ZERO * POINTERS / ELEMENTS);
 }
 
 static constexpr BitsPerElementTableType BITS_PER_ELEMENT_INCLUDING_PONITERS_TABLE[8] = {

c++/src/capnp/rpc-twoparty-test.c++

@@ -351,13 +351,14 @@ TEST(TwoPartyNetwork, HugeMessage) {
   {
     auto req = client.methodWithDefaultsRequest();
     req.initA(100000000);  // 100 MB
-    KJ_EXPECT_THROW_MESSAGE("larger than the single-message size limit",
-        req.send().wait(ioContext.waitScope));
+
+    KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("larger than the single-message size limit",
+        req.send().ignoreResult().wait(ioContext.waitScope));
   }
 
   // Oversized response fails.
-  KJ_EXPECT_THROW_MESSAGE("larger than the single-message size limit",
-      client.getEnormousStringRequest().send().wait(ioContext.waitScope));
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("larger than the single-message size limit",
+      client.getEnormousStringRequest().send().ignoreResult().wait(ioContext.waitScope));
 
   // Connection is still up.
   {

c++/src/capnp/rpc.c++

@@ -448,6 +448,9 @@ private:
     bool isTailCall = false;
     // Is this a tail call?  If so, we don't expect to receive results in the `Return`.
 
+    bool skipFinish = false;
+    // If true, don't send a Finish message.
+
     inline bool operator==(decltype(nullptr)) const {
       return !isAwaitingReturn && selfRef == nullptr;
     }
@@ -1331,7 +1334,7 @@ private:
             connectionState->questions.find(id), "Question ID no longer on table?");
 
         // Send the "Finish" message (if the connection is not already broken).
-        if (connectionState->connection.is<Connected>()) {
+        if (connectionState->connection.is<Connected>() && !question.skipFinish) {
           auto message = connectionState->connection.get<Connected>()->newOutgoingMessage(
               messageSizeHint<rpc::Finish>());
           auto builder = message->getBody().getAs<rpc::Message>().initFinish();
@@ -1504,6 +1507,14 @@ private:
       question.paramExports = kj::mv(exports);
       question.isTailCall = isTailCall;
 
+      // Make the QuentionRef and result promise.
+      SendInternalResult result;
+      auto paf = kj::newPromiseAndFulfiller<kj::Promise<kj::Own<RpcResponse>>>();
+      result.questionRef = kj::refcounted<QuestionRef>(
+          *connectionState, questionId, kj::mv(paf.fulfiller));
+      question.selfRef = *result.questionRef;
+      result.promise = paf.promise.attach(kj::addRef(*result.questionRef));
+
       // Finish and send.
       callBuilder.setQuestionId(questionId);
       if (isTailCall) {
@@ -1514,18 +1525,13 @@ private:
            callBuilder.getInterfaceId(), callBuilder.getMethodId());
         message->send();
       })) {
-        KJ_LOG(WARNING, *exception);
-        kj::throwRecoverableException(kj::mv(*exception));
+        // We can't safely throw the exception from here since we've already modified the question
+        // table state. We'll have to reject the promise instead.
+        question.isAwaitingReturn = false;
+        question.skipFinish = true;
+        result.questionRef->reject(kj::mv(*exception));
       }
 
-      // Make the result promise.
-      SendInternalResult result;
-      auto paf = kj::newPromiseAndFulfiller<kj::Promise<kj::Own<RpcResponse>>>();
-      result.questionRef = kj::refcounted<QuestionRef>(
-          *connectionState, questionId, kj::mv(paf.fulfiller));
-      question.selfRef = *result.questionRef;
-      result.promise = paf.promise.attach(kj::addRef(*result.questionRef));
-
       // Send and return.
       return kj::mv(result);
     }
@@ -1819,7 +1825,6 @@ private:
           KJ_CONTEXT("returning from RPC call", interfaceId, methodId);
           exports = kj::downcast<RpcServerResponseImpl>(*KJ_ASSERT_NONNULL(response)).send();
         })) {
-          KJ_LOG(WARNING, *exception);
           responseSent = false;
           sendErrorReturn(kj::mv(*exception));
           return;
@@ -2268,7 +2273,7 @@ private:
 
     // Add the answer to the answer table for pipelining and send the response.
     auto& answer = answers[answerId];
-    KJ_REQUIRE(!answer.active, "questionId is already in use") {
+    KJ_REQUIRE(!answer.active, "questionId is already in use", answerId) {
       return;
     }
 

c++/src/capnp/test-util.h

@@ -35,20 +35,6 @@
 #include "dynamic.h"
 #endif  // !CAPNP_LITE
 
-#if KJ_NO_EXCEPTIONS
-#undef EXPECT_ANY_THROW
-#define EXPECT_ANY_THROW(code) EXPECT_DEATH(code, ".")
-#endif
-
-#define EXPECT_NONFATAL_FAILURE(code) \
-  EXPECT_TRUE(kj::runCatchingExceptions([&]() { code; }) != nullptr);
-
-#ifdef KJ_DEBUG
-#define EXPECT_DEBUG_ANY_THROW EXPECT_ANY_THROW
-#else
-#define EXPECT_DEBUG_ANY_THROW(EXP)
-#endif
-
 // TODO(cleanup): Auto-generate stringification functions for union discriminants.
 namespace capnproto_test {
 namespace capnp {

c++/src/kj/async-inl.h

@@ -869,6 +869,26 @@ T Promise<T>::wait(WaitScope& waitScope) {
   }
 }
 
+template <>
+inline void Promise<void>::wait(WaitScope& waitScope) {
+  // Override <void> case to use throwRecoverableException().
+
+  _::ExceptionOr<_::Void> result;
+
+  waitImpl(kj::mv(node), result, waitScope);
+
+  if (result.value != nullptr) {
+    KJ_IF_MAYBE(exception, result.exception) {
+      throwRecoverableException(kj::mv(*exception));
+    }
+  } else KJ_IF_MAYBE(exception, result.exception) {
+    throwRecoverableException(kj::mv(*exception));
+  } else {
+    // Result contained neither a value nor an exception?
+    KJ_UNREACHABLE;
+  }
+}
+
 template <typename T>
 ForkedPromise<T> Promise<T>::fork() {
   return ForkedPromise<T>(false, refcounted<_::ForkHub<_::FixVoid<T>>>(kj::mv(node)));

c++/src/kj/async-test.c++

@@ -357,11 +357,6 @@ TEST(Async, SeparateFulfillerChained) {
   EXPECT_EQ(123, pair.promise.wait(waitScope));
 }
 
-#if KJ_NO_EXCEPTIONS
-#undef EXPECT_ANY_THROW
-#define EXPECT_ANY_THROW(code) EXPECT_DEATH(code, ".")
-#endif
-
 TEST(Async, SeparateFulfillerDiscarded) {
   EventLoop loop;
   WaitScope waitScope(loop);

c++/src/kj/common-test.c++

@@ -245,13 +245,7 @@ TEST(Common, Downcast) {
 
   EXPECT_EQ(&bar, &downcast<Bar>(foo));
 #if defined(KJ_DEBUG) && !KJ_NO_RTTI
-#if KJ_NO_EXCEPTIONS
-#ifdef KJ_DEBUG
-  EXPECT_DEATH_IF_SUPPORTED(downcast<Baz>(foo), "Value cannot be downcast");
-#endif
-#else
-  EXPECT_ANY_THROW(downcast<Baz>(foo));
-#endif
+  KJ_EXPECT_THROW_MESSAGE("Value cannot be downcast", downcast<Baz>(foo));
 #endif
 
 #if KJ_NO_RTTI

c++/src/kj/compat/gtest.h

@@ -98,8 +98,22 @@ private:
 
 #define ADD_FAILURE() ::kj::AddFailureAdapter(__FILE__, __LINE__)
 
+#if KJ_NO_EXCEPTIONS
+#define EXPECT_ANY_THROW(code) \
+    KJ_EXPECT(::kj::_::expectFatalThrow(nullptr, nullptr, [&]() { code; }))
+#else
 #define EXPECT_ANY_THROW(code) \
     KJ_EXPECT(::kj::runCatchingExceptions([&]() { code; }) != nullptr)
+#endif
+
+#define EXPECT_NONFATAL_FAILURE(code) \
+  EXPECT_TRUE(kj::runCatchingExceptions([&]() { code; }) != nullptr);
+
+#ifdef KJ_DEBUG
+#define EXPECT_DEBUG_ANY_THROW EXPECT_ANY_THROW
+#else
+#define EXPECT_DEBUG_ANY_THROW(EXP)
+#endif
 
 #define TEST(x, y) KJ_TEST("legacy test: " #x "/" #y)
 

c++/src/kj/exception-test.c++

@@ -97,11 +97,7 @@ TEST(Exception, UnwindDetector) {
 
 #if !__MINGW32__  // Inexplicably crashes when exception is thrown from constructor.
 TEST(Exception, ExceptionCallbackMustBeOnStack) {
-#if KJ_NO_EXCEPTIONS
-  EXPECT_DEATH_IF_SUPPORTED(new ExceptionCallback, "must be allocated on the stack");
-#else
-  EXPECT_ANY_THROW(new ExceptionCallback);
-#endif
+  KJ_EXPECT_THROW_MESSAGE("must be allocated on the stack", new ExceptionCallback);
 }
 #endif  // !__MINGW32__
 

c++/src/kj/mutex-test.c++

@@ -42,20 +42,6 @@ inline void delay() { Sleep(10); }
 inline void delay() { usleep(10000); }
 #endif
 
-#if KJ_NO_EXCEPTIONS
-#undef EXPECT_ANY_THROW
-#define EXPECT_ANY_THROW(code) EXPECT_DEATH(code, ".")
-#define EXPECT_NONFATAL_FAILURE(code) code
-#else
-#define EXPECT_NONFATAL_FAILURE EXPECT_ANY_THROW
-#endif
-
-#ifdef KJ_DEBUG
-#define EXPECT_DEBUG_ANY_THROW EXPECT_ANY_THROW
-#else
-#define EXPECT_DEBUG_ANY_THROW(EXP)
-#endif
-
 TEST(Mutex, MutexGuarded) {
   MutexGuarded<uint> value(123);
 

c++/src/kj/string-test.c++

@@ -86,22 +86,22 @@ TEST(String, parseAs) {
   EXPECT_TRUE(isNaN(StringPtr("nan").parseAs<double>()));
   EXPECT_TRUE(isNaN(StringPtr("NAN").parseAs<double>()));
   EXPECT_TRUE(isNaN(StringPtr("NaN").parseAs<double>()));
-  KJ_EXPECT_THROW_MESSAGE("not contain valid", StringPtr("").parseAs<double>());
-  KJ_EXPECT_THROW_MESSAGE("not contain valid", StringPtr("a").parseAs<double>());
-  KJ_EXPECT_THROW_MESSAGE("not contain valid", StringPtr("1a").parseAs<double>());
-  KJ_EXPECT_THROW_MESSAGE("not contain valid", StringPtr("+-1").parseAs<double>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("not contain valid", StringPtr("").parseAs<double>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("not contain valid", StringPtr("a").parseAs<double>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("not contain valid", StringPtr("1a").parseAs<double>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("not contain valid", StringPtr("+-1").parseAs<double>());
 
   EXPECT_EQ(StringPtr("1").parseAs<float>(), 1.0);
 
   EXPECT_EQ(StringPtr("1").parseAs<int64_t>(), 1);
   EXPECT_EQ(StringPtr("9223372036854775807").parseAs<int64_t>(), 9223372036854775807LL);
   EXPECT_EQ(StringPtr("-9223372036854775808").parseAs<int64_t>(), -9223372036854775808ULL);
-  KJ_EXPECT_THROW_MESSAGE("out-of-range", StringPtr("9223372036854775808").parseAs<int64_t>());
-  KJ_EXPECT_THROW_MESSAGE("out-of-range", StringPtr("-9223372036854775809").parseAs<int64_t>());
-  KJ_EXPECT_THROW_MESSAGE("not contain valid", StringPtr("").parseAs<int64_t>());
-  KJ_EXPECT_THROW_MESSAGE("not contain valid", StringPtr("a").parseAs<int64_t>());
-  KJ_EXPECT_THROW_MESSAGE("not contain valid", StringPtr("1a").parseAs<int64_t>());
-  KJ_EXPECT_THROW_MESSAGE("not contain valid", StringPtr("+-1").parseAs<int64_t>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("out-of-range", StringPtr("9223372036854775808").parseAs<int64_t>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("out-of-range", StringPtr("-9223372036854775809").parseAs<int64_t>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("not contain valid", StringPtr("").parseAs<int64_t>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("not contain valid", StringPtr("a").parseAs<int64_t>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("not contain valid", StringPtr("1a").parseAs<int64_t>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("not contain valid", StringPtr("+-1").parseAs<int64_t>());
   EXPECT_EQ(StringPtr("010").parseAs<int64_t>(), 10);
   EXPECT_EQ(StringPtr("0010").parseAs<int64_t>(), 10);
   EXPECT_EQ(StringPtr("0x10").parseAs<int64_t>(), 16);
@@ -113,24 +113,24 @@ TEST(String, parseAs) {
   EXPECT_EQ(StringPtr("1").parseAs<uint64_t>(), 1);
   EXPECT_EQ(StringPtr("0").parseAs<uint64_t>(), 0);
   EXPECT_EQ(StringPtr("18446744073709551615").parseAs<uint64_t>(), 18446744073709551615ULL);
-  KJ_EXPECT_THROW_MESSAGE("out-of-range", StringPtr("-1").parseAs<uint64_t>());
-  KJ_EXPECT_THROW_MESSAGE("out-of-range", StringPtr("18446744073709551616").parseAs<uint64_t>());
-  KJ_EXPECT_THROW_MESSAGE("not contain valid", StringPtr("").parseAs<uint64_t>());
-  KJ_EXPECT_THROW_MESSAGE("not contain valid", StringPtr("a").parseAs<uint64_t>());
-  KJ_EXPECT_THROW_MESSAGE("not contain valid", StringPtr("1a").parseAs<uint64_t>());
-  KJ_EXPECT_THROW_MESSAGE("not contain valid", StringPtr("+-1").parseAs<uint64_t>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("out-of-range", StringPtr("-1").parseAs<uint64_t>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("out-of-range", StringPtr("18446744073709551616").parseAs<uint64_t>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("not contain valid", StringPtr("").parseAs<uint64_t>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("not contain valid", StringPtr("a").parseAs<uint64_t>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("not contain valid", StringPtr("1a").parseAs<uint64_t>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("not contain valid", StringPtr("+-1").parseAs<uint64_t>());
 
   EXPECT_EQ(StringPtr("1").parseAs<int32_t>(), 1);
   EXPECT_EQ(StringPtr("2147483647").parseAs<int32_t>(), 2147483647);
   EXPECT_EQ(StringPtr("-2147483648").parseAs<int32_t>(), -2147483648);
-  KJ_EXPECT_THROW_MESSAGE("out-of-range", StringPtr("2147483648").parseAs<int32_t>());
-  KJ_EXPECT_THROW_MESSAGE("out-of-range", StringPtr("-2147483649").parseAs<int32_t>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("out-of-range", StringPtr("2147483648").parseAs<int32_t>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("out-of-range", StringPtr("-2147483649").parseAs<int32_t>());
 
   EXPECT_EQ(StringPtr("1").parseAs<uint32_t>(), 1);
   EXPECT_EQ(StringPtr("0").parseAs<uint32_t>(), 0U);
   EXPECT_EQ(StringPtr("4294967295").parseAs<uint32_t>(), 4294967295U);
-  KJ_EXPECT_THROW_MESSAGE("out-of-range", StringPtr("-1").parseAs<uint32_t>());
-  KJ_EXPECT_THROW_MESSAGE("out-of-range", StringPtr("4294967296").parseAs<uint32_t>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("out-of-range", StringPtr("-1").parseAs<uint32_t>());
+  KJ_EXPECT_THROW_RECOVERABLE_MESSAGE("out-of-range", StringPtr("4294967296").parseAs<uint32_t>());
 
   EXPECT_EQ(StringPtr("1").parseAs<int16_t>(), 1);
   EXPECT_EQ(StringPtr("1").parseAs<uint16_t>(), 1);

c++/src/kj/string.c++

@@ -40,25 +40,26 @@ bool isHex(const char *s) {
 }
 
 long long parseSigned(const StringPtr& s, long long min, long long max) {
-  KJ_REQUIRE(s != nullptr, "String does not contain valid number", s);
+  KJ_REQUIRE(s != nullptr, "String does not contain valid number", s) { return 0; }
   char *endPtr;
   errno = 0;
   auto value = strtoll(s.begin(), &endPtr, isHex(s.cStr()) ? 16 : 10);
-  KJ_REQUIRE(endPtr == s.end(), "String does not contain valid number", s);
-  KJ_REQUIRE(errno != ERANGE, "Value out-of-range", s);
-  KJ_REQUIRE(value >= min && value <= max, "Value out-of-range", value, min, max);
+  KJ_REQUIRE(endPtr == s.end(), "String does not contain valid number", s) { return 0; }
+  KJ_REQUIRE(errno != ERANGE, "Value out-of-range", s) { return 0; }
+  KJ_REQUIRE(value >= min && value <= max, "Value out-of-range", value, min, max) { return 0; }
   return value;
 }
 
 unsigned long long parseUnsigned(const StringPtr& s, unsigned long long max) {
-  KJ_REQUIRE(s != nullptr, "String does not contain valid number", s);
+  KJ_REQUIRE(s != nullptr, "String does not contain valid number", s) { return 0; }
   char *endPtr;
   errno = 0;
   auto value = strtoull(s.begin(), &endPtr, isHex(s.cStr()) ? 16 : 10);
-  KJ_REQUIRE(endPtr == s.end(), "String does not contain valid number", s);
-  KJ_REQUIRE(errno != ERANGE, "Value out-of-range", s);
-  KJ_REQUIRE(value <= max, "Value out-of-range", value, max);
-  KJ_REQUIRE(s[0] != '-', "Value out-of-range", s); //strtoull("-1") does not fail with ERANGE
+  KJ_REQUIRE(endPtr == s.end(), "String does not contain valid number", s) { return 0; }
+  KJ_REQUIRE(errno != ERANGE, "Value out-of-range", s) { return 0; }
+  KJ_REQUIRE(value <= max, "Value out-of-range", value, max) { return 0; }
+  //strtoull("-1") does not fail with ERANGE
+  KJ_REQUIRE(s[0] != '-', "Value out-of-range", s) { return 0; }
   return value;
 }
 
@@ -75,11 +76,11 @@ T parseInteger(const StringPtr& s) {
 }
 
 double parseDouble(const StringPtr& s) {
-  KJ_REQUIRE(s != nullptr, "String does not contain valid number", s);
+  KJ_REQUIRE(s != nullptr, "String does not contain valid number", s) { return 0; }
   char *endPtr;
   errno = 0;
   auto value = strtod(s.begin(), &endPtr);
-  KJ_REQUIRE(endPtr == s.end(), "String does not contain valid floating number", s);
+  KJ_REQUIRE(endPtr == s.end(), "String does not contain valid floating number", s) { return 0; }
   return value;
 }
 

c++/src/kj/test.c++

@@ -28,6 +28,9 @@
 #include <string.h>
 #ifndef _WIN32
 #include <sys/mman.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/wait.h>
 #endif
 
 namespace kj {
@@ -59,7 +62,7 @@ TestCase::~TestCase() {
 
 namespace _ {  // private
 
-bool hasSubstring(kj::StringPtr haystack, kj::StringPtr needle) {
+bool hasSubstring(StringPtr haystack, StringPtr needle) {
   // TODO(perf): This is not the best algorithm for substring matching.
   if (needle.size() <= haystack.size()) {
     for (size_t i = 0; i <= haystack.size() - needle.size(); i++) {
@@ -96,6 +99,74 @@ void LogExpectation::logMessage(
 
 // =======================================================================================
 
+namespace {
+
+class FatalThrowExpectation: public ExceptionCallback {
+public:
+  FatalThrowExpectation(Maybe<Exception::Type> type,
+                        Maybe<StringPtr> message)
+      : type(type), message(message) {}
+
+  virtual void onFatalException(Exception&& exception) {
+    KJ_IF_MAYBE(expectedType, type) {
+      if (exception.getType() != *expectedType) {
+        KJ_LOG(ERROR, "threw exception of wrong type", exception, *expectedType);
+        _exit(1);
+      }
+    }
+    KJ_IF_MAYBE(expectedSubstring, message) {
+      if (!hasSubstring(exception.getDescription(), *expectedSubstring)) {
+        KJ_LOG(ERROR, "threw exception with wrong message", exception, *expectedSubstring);
+        _exit(1);
+      }
+    }
+    _exit(0);
+  }
+
+private:
+  Maybe<Exception::Type> type;
+  Maybe<StringPtr> message;
+};
+
+}  // namespace
+
+bool expectFatalThrow(kj::Maybe<Exception::Type> type, kj::Maybe<StringPtr> message,
+                      Function<void()> code) {
+#if _WIN32
+  // We don't support death tests on Windows due to lack of efficient fork.
+  return true;
+#else
+  pid_t child;
+  KJ_SYSCALL(child = fork());
+  if (child == 0) {
+    KJ_DEFER(_exit(1));
+    FatalThrowExpectation expectation(type, message);
+    KJ_IF_MAYBE(e, kj::runCatchingExceptions([&]() {
+      code();
+    })) {
+      KJ_LOG(ERROR, "a non-fatal exception was thrown, but we expected fatal", *e);
+    } else {
+      KJ_LOG(ERROR, "no fatal exception was thrown");
+    }
+  }
+
+  int status;
+  KJ_SYSCALL(waitpid(child, &status, 0));
+
+  if (WIFEXITED(status)) {
+    return WEXITSTATUS(status) == 0;
+  } else if (WIFSIGNALED(status)) {
+    KJ_FAIL_EXPECT("subprocess crashed without throwing exception", WTERMSIG(status));
+    return false;
+  } else {
+    KJ_FAIL_EXPECT("subprocess neiter excited nor crashed?", status);
+    return false;
+  }
+#endif
+}
+
+// =======================================================================================
+
 GlobFilter::GlobFilter(const char* pattern): pattern(heapString(pattern)) {}
 GlobFilter::GlobFilter(ArrayPtr<const char> pattern): pattern(heapString(pattern)) {}
 

c++/src/kj/test.h

@@ -28,6 +28,7 @@
 
 #include "debug.h"
 #include "vector.h"
+#include "function.h"
 
 namespace kj {
 
@@ -74,7 +75,7 @@ private:
   if (cond); else KJ_FAIL_EXPECT("failed: expected " #cond, ##__VA_ARGS__)
 #endif
 
-#define KJ_EXPECT_THROW(type, code) \
+#define KJ_EXPECT_THROW_RECOVERABLE(type, code) \
   do { \
     KJ_IF_MAYBE(e, ::kj::runCatchingExceptions([&]() { code; })) { \
       KJ_EXPECT(e->getType() == ::kj::Exception::Type::type, \
@@ -84,7 +85,7 @@ private:
     } \
   } while (false)
 
-#define KJ_EXPECT_THROW_MESSAGE(message, code) \
+#define KJ_EXPECT_THROW_RECOVERABLE_MESSAGE(message, code) \
   do { \
     KJ_IF_MAYBE(e, ::kj::runCatchingExceptions([&]() { code; })) { \
       KJ_EXPECT(::kj::_::hasSubstring(e->getDescription(), message), \
@@ -94,6 +95,20 @@ private:
     } \
   } while (false)
 
+#if KJ_NO_EXCEPTIONS
+#define KJ_EXPECT_THROW(type, code) \
+  do { \
+    KJ_EXPECT(::kj::_::expectFatalThrow(type, nullptr, [&]() { code; })); \
+  } while (false)
+#define KJ_EXPECT_THROW_MESSAGE(message, code) \
+  do { \
+    KJ_EXPECT(::kj::_::expectFatalThrow(nullptr, kj::StringPtr(message), [&]() { code; })); \
+  } while (false)
+#else
+#define KJ_EXPECT_THROW KJ_EXPECT_THROW_RECOVERABLE
+#define KJ_EXPECT_THROW_MESSAGE KJ_EXPECT_THROW_RECOVERABLE_MESSAGE
+#endif
+
 #define KJ_EXPECT_LOG(level, substring) \
   ::kj::_::LogExpectation KJ_UNIQUE_NAME(_kjLogExpectation)(::kj::LogSeverity::level, substring)
 // Expects that a log message with the given level and substring text will be printed within
@@ -105,6 +120,14 @@ namespace _ {  // private
 
 bool hasSubstring(kj::StringPtr haystack, kj::StringPtr needle);
 
+#if KJ_NO_EXCEPTIONS
+bool expectFatalThrow(Maybe<Exception::Type> type, Maybe<StringPtr> message,
+                      Function<void()> code);
+// Expects that the given code will throw a fatal exception matching the given type and/or message.
+// Since exceptions are disabled, the test will fork() and run in a subprocess. On Windows, where
+// fork() is not available, this always returns true.
+#endif
+
 class LogExpectation: public ExceptionCallback {
 public:
   LogExpectation(LogSeverity severity, StringPtr substring);