Closed Bug 1551912 Opened 7 years ago Closed 7 years ago

[wpt-sync] Sync PR 16802 - [LayoutNG] Fix shape exclusion tracking.

Categories

(Core :: CSS Parsing and Computation, defect, P4)

Product:
Core
Component:
CSS Parsing and Computation
Type:
defect

Tracking

()

Status:
RESOLVED FIXED
Milestone:
mozilla69
Tracking Flags:
Tracking Status
firefox69 --- fixed

People

(Reporter: wpt-sync, Unassigned)

References

(
URL
)

Details

(Whiteboard: [wptsync upstream])

Sync web-platform-tests PR 16802 into mozilla-central (this bug is closed when the sync is complete).

PR: https://github.com/web-platform-tests/wpt/pull/16802
Details from upstream follow.

Ian Kilpatrick <ikilpatrick@chromium.org> wrote:

[LayoutNG] Fix shape exclusion tracking.

The DerivedGeometry class gets moved from exclusion-space to
exclusion-space as a fast way of determining layout opportunities (where
lines, etc get placed).

For speed we only allocate "NGShapeExclusions" if we've seen any shapes
within the formatting context.

This crash was due to an inconsistent state of the:
NGExclusionSpaceInternal::track_shape_exclusions_ flag.

"other" NGExclusionSpaceInternal

  • derived_geometry_ = (non-null)
  • track_shape_exclusions_ = false
  • num_exclusions_ = 1u

"this" NGExclusionSpaceInternal

  • derived_geometry_ = null
  • track_shape_exclusions_ = true
  • num_exclusions_ = 2u (2nd exclusion has shape data).

Within the NGExclusionSpaceInternal::MoveAndUpdateDerivedGeometry method
we moved the derived geometry over to the "this" exclusion space.

However we didn't also move the track_shape_exclusions_ flag as a result
we'd try to add the 2nd shape exclusion, and a NPE was hit.

Bug: 962135, 962272, 962052
Change-Id: Id095bd2924f83ba6b2dbe90446d1f4613de09933
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1610021
Commit-Queue: Ian Kilpatrick \<ikilpatrick@chromium.org>
Reviewed-by: Morten Stenshorne \<mstensho@chromium.org>
Reviewed-by: Christian Biesinger \<cbiesinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#659678}

Component: web-platform-tests → CSS Parsing and Computation
Product: Testing → Core
Failed to get results from try push
Pushed by james@hoppipolla.co.uk: https://hg.mozilla.org/integration/mozilla-inbound/rev/e97e97ebe968 [wpt PR 16802] - [LayoutNG] Fix shape exclusion tracking., a=testonly

https://hg.mozilla.org/mozilla-central/rev/e97e97ebe968

Status: NEW → RESOLVED
Closed: 7 years ago
status-firefox69: --- → fixed
Resolution: --- → FIXED
Target Milestone: --- → mozilla69
Whiteboard: [wptsync downstream] → [wptsync upstream]
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