Bug 212546 – REGRESSION (r260306): Compatibility issue leading to crash on macOS games

• Component: WebKit Misc.
• Status: RESOLVED FIXED

[David Kilzer (:ddkilzer)]

Compatibility issue leading to crash on macOS games.

Changing instance variables to __weak in the _WebSafeForwarder class caused a couple of macOS games to crash just before starting play.

The fix is to remove the __weak attribute, which effectively changes them back to __unsafe_unretained.

Caused by:

    Bug 210625: [iOS WK1] -[_WebSafeForwarder asyncForwarder] uses non-static dispatch_once_t predicate
    <https://bugs.webkit.org/show_bug.cgi?id=210625>
    <https://trac.webkit.org/changeset/260306/webkit>

<rdar://problem/62624078>

[David Kilzer (:ddkilzer)]

Created attachment 400620 [details]
Patch v1

[David Kilzer (:ddkilzer)]

Comment on attachment 400620 [details]
Patch v1

View in context: https://bugs.webkit.org/attachment.cgi?id=400620&action=review

> Source/WebKitLegacy/mac/WebView/WebView.mm:569
> +    // Do not not change _target and _defaultTarget to __weak. See <rdar://problem/62624078>.
> +    id _target;
> +    id _defaultTarget;

Should I proactively change these to __unsafe_unretained to future-proof a possible mistake during ARC conversion?

[Brent Fulgham]

Comment on attachment 400620 [details]
Patch v1

View in context: https://bugs.webkit.org/attachment.cgi?id=400620&action=review

r=me

>> Source/WebKitLegacy/mac/WebView/WebView.mm:569
>> +    id _defaultTarget;
> 
> Should I proactively change these to __unsafe_unretained to future-proof a possible mistake during ARC conversion?

Yes, that seems like a good idea.

[David Kilzer (:ddkilzer)]

Created attachment 400627 [details]
Patch for landing

[David Kilzer (:ddkilzer)]

Waiting on EWS before marking cq+.

[David Kilzer (:ddkilzer)]

Comment on attachment 400627 [details]
Patch for landing

TestWebKitAPI.WKWebsiteDataStore.RemoveAndFetchData is failing on api-ios, but it is a WebKit2 test, so this patch can't possibly affect it.  Marking as cq+.

[EWS]

Committed r262330: <https://trac.webkit.org/changeset/262330>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 400627 [details].