A guess would be that it only works on types with internal fields, which are only objecttemplate-sourced objects. That's the only thing that would need any type of user-specified code to run on GC. But that's just a guess. A quick glance at the source doesn't back it up.
On Thu, Oct 6, 2016 at 9:48 AM, Theodore Dubois <[email protected]> wrote: > I don’t think the problem is allocating the handle on the heap, I’m doing > that in my code too. The significant difference between your code and my > code is that I’m using a FunctionTemplate and trying to get a weak callback > on the Functions it creates, and you’re using an ObjectTemplate. When I > changed Function to Object in my code and fixed a few compiler errors, it > worked. > > It seems like it’s pretty easy to get this to work with objects, but much > harder with functions. Does anyone know how to make this work? > > Thanks, > ~Theodore > > > On Oct 5, 2016, at 8:41 PM, Zac Hansen <[email protected]> wrote: > > > > Also, here's the somewhat generalized code I use for doing this in my > integration library: > > > > https://github.com/xaxxon/v8toolkit/blob/master/include/v8toolkit.h#L972 > > > > On Wed, Oct 5, 2016 at 8:36 PM, Zac Hansen <[email protected]> wrote: > > Good news is, this program calls the callback. Bad news it crashes, but > I think it demonstrates the general idea. > > > > I believe the problem with your program is that your global with the > weak callback goes away too early. In my program below you can see I'm > allocating the global on the heap (and leaking the crap out of it - but you > can clean it up in the callback) and that makes the callback get called > because the global is still around. > > > > > > > > caveat emptor > > > > > > > > P.S. Posting a compilable program next time makes it easier for me to > help you > > > > > > > > #include <v8.h> > > > > #include <v8-platform.h> > > > > #include <libplatform/libplatform.h> > > > > #include <stdio.h> > > > > > > > > using namespace v8; > > > > > > > > void func_callback(const FunctionCallbackInfo<v8::Value> &data) { > > > > fprintf(stderr, "Here\n"); > > > > } > > > > > > > > void weak_callback(const WeakCallbackInfo<int> &data) { > > > > fprintf(stderr, "weak callback\n"); > > > > } > > > > > > > > > > > > class ArrayBufferAllocator : public v8::ArrayBuffer::Allocator { > > > > public: > > > > inline virtual void* Allocate(size_t length) override { > > > > void* data = AllocateUninitialized(length); > > > > return data == NULL ? data : memset(data, 0, length); > > > > } > > > > inline virtual void* AllocateUninitialized(size_t length) override { > return malloc(length); } > > > > inline virtual void Free(void* data, size_t) override { free(data); } > > > > }; > > > > > > > > > > > > int main() { > > > > V8::InitializeICU(); > > > > Platform *current_platform = v8::platform::CreateDefaultPlatform(); > > > > V8::InitializePlatform(current_platform); > > > > V8::Initialize(); > > > > V8::SetFlagsFromString("--expose_gc", strlen("--expose_gc")); > > > > Isolate::CreateParams params; > > > > params.array_buffer_allocator = new ArrayBufferAllocator(); > > > > Isolate *isolate = Isolate::New(params); > > > > HandleScope hs(isolate); > > > > > > > > Local<Context> context = Context::New(isolate); > > > > > > > > > > > > int iii; // bogus int > > > > Local<ObjectTemplate> ot = ObjectTemplate::New(isolate); > > > > ot->SetInternalFieldCount(1); > > > > > > > > for (int i = 0; ; i++) { > > > > HandleScope hs2(isolate); > > > > Local<Object> obj = ot->NewInstance(context).ToLocalChecked(); > > > > Global<Object> * gobject = new Global<Object>(isolate, obj); > > > > gobject->SetWeak<int>(&iii, weak_callback, > WeakCallbackType::kParameter); > > > > isolate->AdjustAmountOfExternalAllocatedMemory(100000000); > > > > > > > > if (i%1000==0)printf("%d\r", i); > > > > /* context->Global()->Set(context, key, func).FromJust(); */ > > > > /* context->Global()->Delete(context, key).FromJust(); */ > > > > } > > > > > > > > > > > > return 0; > > > > > > On Wed, Oct 5, 2016 at 7:56 PM, <[email protected]> wrote: > > Actually, that didn't work. Any other ideas? Any techniques for > debugging GC (like getting information on where an object is referenced?) > > > > -- > > -- > > v8-users mailing list > > [email protected] > > http://groups.google.com/group/v8-users > > --- > > You received this message because you are subscribed to a topic in the > Google Groups "v8-users" group. > > To unsubscribe from this topic, visit https://groups.google.com/d/ > topic/v8-users/Rshbi2HKYCM/unsubscribe. > > To unsubscribe from this group and all its topics, send an email to > [email protected]. > > For more options, visit https://groups.google.com/d/optout. > > > > > > > > -- > > -- > > v8-users mailing list > > [email protected] > > http://groups.google.com/group/v8-users > > --- > > You received this message because you are subscribed to a topic in the > Google Groups "v8-users" group. > > To unsubscribe from this topic, visit https://groups.google.com/d/ > topic/v8-users/Rshbi2HKYCM/unsubscribe. > > To unsubscribe from this group and all its topics, send an email to > [email protected]. > > For more options, visit https://groups.google.com/d/optout. > > -- > -- > v8-users mailing list > [email protected] > http://groups.google.com/group/v8-users > --- > You received this message because you are subscribed to a topic in the > Google Groups "v8-users" group. > To unsubscribe from this topic, visit https://groups.google.com/d/ > topic/v8-users/Rshbi2HKYCM/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- -- v8-users mailing list [email protected] http://groups.google.com/group/v8-users --- You received this message because you are subscribed to the Google Groups "v8-users" group. 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