Bug 309512 – [macOS arm64] fast/text/glyph-display-lists/glyph-display-list-* are flaky text failures.

• Status: RESOLVED
• Resolution: FIXED
• Component: Text

[Diego De La Toba]

fast/text/glyph-display-lists/glyph-display-list-color.html
fast/text/glyph-display-lists/glyph-display-list-gpu-process-crash.html
fast/text/glyph-display-lists/glyph-display-list-scaled-unshared.html
fast/text/glyph-display-lists/glyph-display-list-shadow-unshared.html
fast/text/glyph-display-lists/glyph-display-list-sharing-colr.html
fast/text/glyph-display-lists/glyph-display-list-svg-unshared.html
are flaky text failures on macOS arm64.


HISTORY:
https://results.webkit.org/?suite=layout-tests&suite=layout-tests&suite=layout-tests&suite=layout-tests&suite=layout-tests&suite=layout-tests&test=fast%2Ftext%2Fglyph-display-lists%2Fglyph-display-list-color.html&test=fast%2Ftext%2Fglyph-display-lists%2Fglyph-display-list-gpu-process-crash.html&test=fast%2Ftext%2Fglyph-display-lists%2Fglyph-display-list-scaled-unshared.html&test=fast%2Ftext%2Fglyph-display-lists%2Fglyph-display-list-shadow-unshared.html&test=fast%2Ftext%2Fglyph-display-lists%2Fglyph-display-list-sharing-colr.html&test=fast%2Ftext%2Fglyph-display-lists%2Fglyph-display-list-svg-unshared.html


BUILD URL:
https://build.webkit.org/#/builders/1716/builds/2288


LAYOUT RESULTS:
https://build.webkit.org/results/Apple-Tahoe-Release-AppleSilicon-WK2-Tests/308904%40main%20(2288)/results.html


REPRODUCTION:
I was able to reproduce the following failures on macOS Tahoe 26.2 with the following:

run-webkit-tests --no-retry --release --iterations 100 -f fast/inline/invalidation-crash-under-memory-pressure.html fast/text/glyph-display-lists/glyph-display-list-color.html fast/text/glyph-display-lists/glyph-display-list-gpu-process-crash.html fast/text/glyph-display-lists/glyph-display-list-scaled-unshared.html fast/text/glyph-display-lists/glyph-display-list-shadow-unshared.html fast/text/glyph-display-lists/glyph-display-list-sharing-colr.html fast/text/glyph-display-lists/glyph-display-list-svg-unshared.html

Note: fast/inline/invalidation-crash-under-memory-pressure.html must precede the tests for failures to occur.

I am going to mark expectations as pass fail while this pends investigation.

[Radar WebKit Bug Importer]

<rdar://problem/172110925>

[Diego De La Toba]

Pull request: https://github.com/WebKit/WebKit/pull/60210

[EWS]

Test gardening commit 308929@main (fec8d9c23bac): <https://commits.webkit.org/308929@main>

Reviewed commits have been landed. Closing PR #60210 and removing active labels.

[Diego De La Toba]

fast/inline/invalidation-crash-under-memory-pressure.html calls internals.beginSimulatedMemoryPressure() but never calls internals.endSimulatedMemoryPressure(), leaving m_isSimulatingMemoryPressure = true across subsequent tests.

When the glyph display list tests run, GlyphDisplayListCache::getDisplayList() checks isUnderMemoryPressure() on every cache access (line 100-106). Because the flag is still set, the cache is cleared and nullptr is returned, causing the tests to fail.

The fix here is to add internals.endSimulatedMemoryPressure() to the test. Putting this up as a PR, please review.

[Diego De La Toba]

Pull request: https://github.com/WebKit/WebKit/pull/60211

[EWS]

Committed 309013@main (f91f808e24d7): <https://commits.webkit.org/309013@main>

Reviewed commits have been landed. Closing PR #60211 and removing active labels.

[Diego De La Toba]

Re-opening for pull request https://github.com/WebKit/WebKit/pull/60298

[EWS]

Committed 309093@main (e03e0b23e81d): <https://commits.webkit.org/309093@main>

Reviewed commits have been landed. Closing PR #60298 and removing active labels.