Created attachment 77506 [details]
Testing a string against a regex of the form /(?:x|^)$/, where x can be any character, crashes WebKit. There can be any number of things separated by |'s. The crash seems to be triggered when the non-capturing parentheses include a ^ and are followed by a $. Also, it seems that the parentheses must be non-capturing.
A regular expression like this gets used in the html5rocks.com website. I'm also attaching a reduced version that just tests a string against /(?:x|^)$/.
I am not able to reproduce this bug in recent changeset 74813. I suspect that this is a duplicate of another bug, possibly https://bugs.webkit.org/show_bug.cgi?id=51284 but I can't reproduce at this time. Will try to reproduce.
*** This bug has been marked as a duplicate of bug 51284 ***