1039454 - "ASSERTION: Computed overflow area must contain frame bounds" in sequence of style changes

Status: RESOLVED FIXED

(Core :: Layout, defect)

Description

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Attachment: test.html

I ran into this while debugging another bug.

The attached testcase fires this assertion on load.

Comment 1

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Attachment: fix

Initially the test sets InitialOverflowProperty for 'outer' to have width 300px. In the second step, we FinishAndStoreOverflow for 'outer' and note that we no longer need a real overflow rect since there is no overflow, but the InitialOverflowProperty is not removed or modified so it's still 300px wide. Then in the third step we trigger an UpdateOverflow change which uses the stale value of InitialOverflowProperty and asserts because it doesn't contain the element's border-box.

Comment 2

[Mats Palmgren (inactive)]

Comment on attachment 8456834 [details] [diff] [review]
fix

s/Remove/Delete/ otherwise you leak the value, right?

r=mats with that

Also, would it be possible to add MOZ_WARN_UNUSED_RESULT on the
Remove declaration to avoid this in the future?

Comment 3

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Er yeah, good point.

(In reply to Mats Palmgren (:mats) from comment #2)
> Also, would it be possible to add MOZ_WARN_UNUSED_RESULT on the
> Remove declaration to avoid this in the future?

Probably. I'll try that.

Comment 4

[Robert O'Callahan (:roc) (email my personal email if necessary)]

https://hg.mozilla.org/integration/mozilla-inbound/rev/9ce2ae3e23f3

Comment 5

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/9ce2ae3e23f3