Bug 165012 – Fix exception scope verification failures in GenericArgumentsInlines.h.

• Status: RESOLVED
• Resolution: FIXED
• Component: JavaScriptCore

[Mark Lam]

Patch coming.

[Mark Lam]

Created attachment 295315 [details]
proposed patch.

[Saam Barati]

Comment on attachment 295315 [details]
proposed patch.

View in context: https://bugs.webkit.org/attachment.cgi?id=295315&action=review

> Source/JavaScriptCore/runtime/GenericArgumentsInlines.h:213
> +            RETURN_IF_EXCEPTION(scope, false);

I wonder if this should be an assertion instead of a return. Why would this fail?

[Mark Lam]

Comment on attachment 295315 [details]
proposed patch.

View in context: https://bugs.webkit.org/attachment.cgi?id=295315&action=review

>> Source/JavaScriptCore/runtime/GenericArgumentsInlines.h:213
>> +            RETURN_IF_EXCEPTION(scope, false);
> 
> I wonder if this should be an assertion instead of a return. Why would this fail?

I think you're right.  As far as I can remember, the reason I added this check was because:
1. putDirectMayBeIndex() may call putDirectIndex() with mode PutDirectIndexLikePutDirect.
2. putDirectIndex() may call putDirectIndexBeyondVectorLength().
3. putDirectIndexBeyondVectorLength() may call putDirectIndexBeyondVectorLengthWithArrayStorage().
4. putDirectIndexBeyondVectorLengthWithArrayStorage() may throw if mode == PutDirectIndexShouldThrow.

So, in our case here, we wouldn't expect an exception because the PutDirectIndexMode is never PutDirectIndexShouldThrow.  I'll change this to an assert.

[Mark Lam]

Created attachment 304729 [details]
Patch for landing.

[Mark Lam]

Thanks for the review.  Landed in r214085: <http://trac.webkit.org/r214085>.