FATAL ERROR: v8::HandleScope::CreateHandle() Cannot create a handle without a HandleScope

[andrewrk]

When testing my native addon with iojs 3 I get

FATAL ERROR: v8::HandleScope::CreateHandle() Cannot create a handle without a HandleScope

I'm following the pattern in test/cpp/objectwraphandle.cpp. The line it crashes on is this one:

v8::Local<v8::Function> cons = Nan::New(constructor);

I tried to run the test to see if it would pass, but #439 happened.

[kkoopa]

You have to actually declare your handle scopes. It should be Nan::HandleScope scope;, since Nan::HandleScope(); immediately destroys the created scope.

[andrewrk]

Here's my code:

Local<Value> GNFile::NewInstance(GrooveFile *file) {
    Nan::EscapableHandleScope scope;

    Local<Function> cons = Nan::New(constructor);
    Local<Object> instance = cons->NewInstance();

    GNFile *gn_file = node::ObjectWrap::Unwrap<GNFile>(instance);
    gn_file->file = file;

    return scope.Escape(instance);
}

Backtrace of the abort:

#1  0x00007ffff5f177ea in abort ()
   from /nix/store/qlxp7vb63fp8kx5vk9a0y3rj8svbvl27-glibc-2.21/lib/libc.so.6
#2  0x0000000000b44bf3 in node::OnFatalError(char const*, char const*) ()
#3  0x000000000064b095 in v8::Utils::ReportApiFailure(char const*, char const*) ()
#4  0x00000000007f7cff in v8::internal::HandleScope::Extend(v8::internal::Isolate*) ()
#5  0x000000000064be28 in v8::EscapableHandleScope::EscapableHandleScope(v8::Isolate*) ()
#6  0x00007ffff3aabfc7 in Nan::EscapableHandleScope::EscapableHandleScope (
    this=0x7fffffff8e90) at ../node_modules/nan/nan.h:352
#7  0x00007ffff3aaa305 in GNFile::NewInstance (file=0x7fffd40008c0) at ../src/file.cc:46

file.cc:46 is Nan::EscapableHandleScope scope;

[andrewrk]

you nailed it though, I replaced all the Nan::HandleScope() in my codebase with Nan::HandleScope scope and that fixed the problem. thanks!

[jain009deep]

Any solution to above problem? I am getting same error while using "java" node module with node v 4.x.x. It was ok til node v 0.10.36.

[kkoopa]

Declare HandleScopes where necessary.

[eelcocramer]

I have a similar issue where this error occurs in the line where I declare an EscapableHandleScope. When I declare a HandleScope before that line the error doesn't occur.

It doesn't make sense to have to declare a HandleScope before an EscapableHandleScope does it?

Code can be found here

[kkoopa]

No, that does not make sense. Let's see now. There's a mention of some issue workaround, that should not happen or be necessary. It seems to be a remnant of something old, there is no reason it would return a bad handle in this day and age. Remove that and the EscapableHandleScope and you should be all set. Also, the scopes in the NAN_METHODs are unnecessary and can be removed.

[kkoopa]

Actually, that code has been wrong forever. Already this commit was an incorrect fix: eelcocramer/node-bluetooth-serial-port@7eeb85f

[eelcocramer]

Thanks a lot for the feedback!

[kkoopa]

I think I saw similar weirdness (besides that strange 'fix') pop up in other places while skimming through the code base, so better do a thorough inspection of the code for all platforms.

Every function not directly exposed to V8 which creates handles (or does anything with V8 to be sure) should have a HandleScope or EscapableHandleScope. Save for doing weird stuff with nested scopes in scopes, EscapableHandleScope should only be used when returning handles from the function. If it returns void or a non-V8 type, use HandleScope. Having scopes is of utmost importance in libuv callbacks, without them you get the titular fatal error.