Bug 141324 – REGRESSION(r179706): Caused memory corruption on some tests

• Status: RESOLVED
• Resolution: FIXED
• Component: Layout and Rendering

[WebKit Commit Bot]

http://trac.webkit.org/changeset/179706 broke the build:
Caused memory corruption on some tests (Requested by _ap_ on #webkit).

This is an automatic bug report generated by webkitbot. If this bug
report was created because of a flaky test, please file a bug for the flaky
test (if we don't already have one on file) and dup this bug against that bug
so that we can track how often these flaky tests fail.

[WebKit Commit Bot]

Created attachment 246150 [details]
ROLLOUT of r179706

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[Maciej Stachowiak]

Created attachment 246152 [details]
Patch

[Alexey Proskuryakov]

Comment on attachment 246152 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=246152&action=review

> Source/WebCore/rendering/RenderLineBoxList.cpp:390
> +        if (auto prevBox = box->prevRootBox())

There are different opinions on this, however I find it much preferable to see which classes I'm dealing with (i.e., I'd write this as RootInlineBox* previousBox = box->prevRootBox()).

> Source/WebCore/rendering/RenderLineBoxList.cpp:392
> +        // FIXME: Always dirty the next line. This is only strictly necessary some of the time, 

This sounds like a command (as if we needed always dirty the next line, but didn't).

> Source/WebCore/rendering/RenderLineBoxList.cpp:394
> +        // but it's hard to safely and completely compute the conditions under which it's safe 
> +        // not to.

I'd omit this, as it doesn't explain what is hard about this, and is thus unhelpful to the reader.

[Alexey Proskuryakov]

Ping?

[zalan]

(In reply to comment #3)
> Comment on attachment 246152 [details]
> Patch
> 
> View in context:
> https://bugs.webkit.org/attachment.cgi?id=246152&action=review
> 
> > Source/WebCore/rendering/RenderLineBoxList.cpp:390
> > +        if (auto prevBox = box->prevRootBox())
> 
> There are different opinions on this, however I find it much preferable to
> see which classes I'm dealing with (i.e., I'd write this as RootInlineBox*
> previousBox = box->prevRootBox()).
I am in favor of not over-using auto, but I think in this case auto is acceptable as the method (prev/nextRootBox()) hints that the return type is a root box.

Hopefully the perf bots will catch if there's any inline layout performance impact of this change.

[Maciej Stachowiak]

Committed r179750: <http://trac.webkit.org/changeset/179750>