Thanks.  Any tip in debugging this kind of failures?  I don't seem to get a 
stack even though I'm using debug build both for v8 and my embedding app.

On Monday, October 5, 2015 at 1:59:46 PM UTC-7, Jakob Kummerow wrote:
>
> The whole point of a MaybeLocal is that it *may *(or may not) contain a 
> value. Calling .ToLocalChecked() on it is unsafe, unless you happen to know 
> that it can't be empty. shell.cc:416 
> <https://chromium.googlesource.com/v8/v8/+/master/samples/shell.cc#416> 
> is doing it wrong. d8.cc:883 
> <https://chromium.googlesource.com/v8/v8/+/master/src/d8.cc#883> is doing 
> it right.
>
> A callback throwing an exception is the canonical example of a function 
> that possibly returns no value, in which case its MaybeLocal return value 
> is empty. The reason we've introduced MaybeLocals is so embedders can be 
> sure they've covered all the places where they have to check for exceptions 
> being thrown, since they can't accidentally convert from MaybeLocal to 
> Local without explicitly checking for emptiness.
>
>
> On Mon, Oct 5, 2015 at 9:25 PM, Jane Chen <[email protected] <javascript:>
> > wrote:
>
>> [jchen@jchen-z620 x64.release]$ ./shell
>> V8 version 4.7.0 (candidate) [sample shell]
>> > read();
>> (shell):1: Bad parameters
>> read();
>> ^
>>
>> #
>> # Fatal error in v8::ToLocalChecked
>> # Empty MaybeLocal.
>> #
>>
>> Illegal instruction (core dumped)
>>
>> This is with a build made with either:
>>
>> make -j8 x64.debug -werror=no GYPFLAGS="-Dv8_use_external_startup_data=0 
>> -Dcomponent=shared_library"
>>
>> or:
>>
>> make -j8 x64.release -werror=no 
>> GYPFLAGS="-Dv8_use_external_startup_data=0 -Dcomponent=shared_library"
>>
>> I see this with my embedding application as well as long as I throw an 
>> exception from a callback.  Am I missing something or should I use a more 
>> stable branch?  If so, which branch of v8 works with the above?
>>
>> Thanks in advance.
>>
>> -- 
>> -- 
>> v8-users mailing list
>> [email protected] <javascript:>
>> http://groups.google.com/group/v8-users
>> --- 
>> You received this message because you are subscribed to the Google Groups 
>> "v8-users" 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-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.
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.

Reply via email to