I should have mentioned my original bug report against V8: https://bugs.chromium.org/p/v8/issues/detail?id=4830
The stacktrace (with node running in debug mode) would be: https://gist.github.com/bpasero/fb5f8a6022b37f7b1a34 I am sitting in the Visual Studio debugger right at the FAIL call and can examine the object. Typing "this" just returns that it is a v8::internal::Object with a value of 0x0baffedf {...} Btw I am able to run IsOddball() and that returns false. On Tuesday, April 12, 2016 at 7:31:23 PM UTC+2, Jochen Eisinger wrote: > > and the value of "this" when you hit the FATAL() > > On Tue, Apr 12, 2016 at 7:33 PM Jochen Eisinger <[email protected] > <javascript:>> wrote: > >> Could you post a stack trace that leads to the FATAL()? >> >> On Tue, Apr 12, 2016 at 7:27 PM Ben Noordhuis <[email protected] >> <javascript:>> wrote: >> >>> On Tue, Apr 12, 2016 at 7:11 PM, <[email protected] <javascript:>> >>> wrote: >>> > Hi, >>> > >>> > we (Microsoft VS Code team) are tracking down a very weird native >>> crash in >>> > our use of node.js (5.10.0, V8 46) that only ever shows up since we >>> updated >>> > from node.js 4.x (V8 45). It seems that changes (around the Garbace >>> > Collector?) in V8 46 have an impact to the crash. >>> > >>> > Specifically, we are using the node-weak module >>> > (https://github.com/TooTallNate/node-weak) to be able to get weak >>> references >>> > onto JavaScript objects. This used to work relatively good in node.js >>> 4.x, >>> > but with node.js 5.x we suddenly get the entire node.js program to >>> terminate >>> > with a fatal crash. >>> > >>> > Today we were finally able to track the location of where the crash >>> > originates and it seems to happen when our application simply calls >>> into a >>> > property of the object that is weakly referenced. This call at one >>> point >>> > reaches the following assertion: >>> > >>> > void Object::VerifyApiCallResultType() { >>> > #if DEBUG >>> > if (!(IsSmi() || IsString() || IsSymbol() || IsSpecObject() || >>> > IsHeapNumber() || IsSimd128Value() || IsUndefined() || >>> IsTrue() || >>> > IsFalse() || IsNull())) { >>> > FATAL("API call returned invalid object"); >>> > } >>> > #endif // DEBUG >>> > } >>> > >>> > >>> > The process terminates from the FATAL call, as none of the previous >>> checks >>> > in this method hold. >>> > >>> > >>> > Now, the interesting question is: How would it be possible to have a JS >>> > object where calling properties on it would fail in such a fatal way? >>> It >>> > seems to us that the object we are calling a property on is a pointer >>> to a >>> > location in memory where no V8 object exists anymore. It almost seems >>> that >>> > the object was garbage collected (or moved to another address?) >>> without the >>> > JS side (or more specifically the node-weak side) getting to know. >>> > >>> > >>> > Since this only reproduces with using node-weak, it seems very likely >>> that >>> > there is an issue with either node-weak or NAN. In fact, node-weak is >>> > calling into SetWeak() >>> > ( >>> https://github.com/TooTallNate/node-weak/blob/master/src/weakref.cc#L174 >>> ) >>> > and relies on the fact that the callback passed in is triggered and >>> maybe >>> > this callback is not triggered anymore in a sync fashion but rather >>> async? >>> > >>> > >>> > I would appreciate some pointers if there is something that could have >>> > probably changed in V8 46 that could have an impact on this. >>> >>> If you have a simple test case (stress on 'simple'), I'll have a look. >>> >>> -- >>> -- >>> v8-dev mailing list >>> [email protected] <javascript:> >>> http://groups.google.com/group/v8-dev >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "v8-dev" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected] <javascript:>. >>> For more options, visit https://groups.google.com/d/optout. >>> >> -- -- v8-dev mailing list [email protected] http://groups.google.com/group/v8-dev --- You received this message because you are subscribed to the Google Groups "v8-dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
