Fix font cache assertion crashes on login screen - #391
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Fix a CTD encountered upon teleport.
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📝 SummarySummary by CodeRabbit
WalkthroughThe changes refresh shaping-cache mutation snapshots, reset password-field font buffers when displayed text changes, defer region capability completion to the main coroutine, and leave an unresolved merge conflict in the text-cache header. ChangesFont rendering updates
Region capability completion
Estimated code review effort: 3 (Moderate) | ~20 minutes Merge Risk: 🟠 High · up to The font-cache fixes are not merge-ready because the changed header cannot compile, and deferred capability completion may incorrectly complete a superseded region request. Suggested reviewers: Poem
🚥 Pre-merge checks | ✅ 4 | ❌ 1❌ Failed checks (1 warning)
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Inline comments:
In `@indra/llrender/llfonttextcache.h`:
- Line 104: Update the debug recording and mismatch-reporting logic in the text
cache, including mRecordedText uses, so password content is never stored or
logged: retain only length and the existing fingerprint metadata, and guard all
mRecordedText references with LL_DEBUG because the member is unavailable in
non-debug builds.
- Line 104: Guard the mRecordedText accesses in
ALFontCacheKey::sameTextAsRecorded and the nearby assignment with LL_DEBUG,
while keeping hash updates unconditional. Ensure release and RelWithDebInfo
builds compile without referencing the debug-only member.
- Around line 111-114: Update the sameTextAsRecorded mismatch warning in the
relevant cache comparison method to avoid logging mRecordedText or the new text
contents; report only their lengths or non-reversible fingerprints while
preserving the mismatch warning.
In `@indra/newview/llviewerregion.cpp`:
- Around line 399-411: Update the deferred completion flow in
LLViewerRegion::setSeedCapability to capture the responder ID that passed the
stale-response check alongside regionHandle. In the postToMainCoro lambda,
compare the captured ID with the region’s current mHttpResponderID and return on
mismatch before calling setCapabilitiesReceived(true).
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indra/llrender/llfontgl.cppindra/llrender/llfonttextcache.hindra/llui/lllineeditor.cppindra/newview/llaisapi.cppindra/newview/llinventorymodel.cppindra/newview/llviewerregion.cpp
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Two assertion failures were crashing the viewer in debug builds during the login screen render. The first assert (llfonttextcache.cpp: sameTextAsRecorded) was caused by LLLineEditor's password masking path sharing a single LLFontTextCache instance across both the real password text and the bullet substitution string. Fix resets the three font buffers (pre-selection, selection, post-selection) before and after the mDrawAsterixes text swap so each render pass sees a consistent string for its cache entry. The second assert (llfontgl.cpp: mutation_snapshot == ALFontShaping::cacheMutationCount) was caused by glyph rasterization during the render loop triggering a ~LLFontFreetype destructor chain (via atlas eviction → LLPointer drop → clearCacheForFace), which bumped the shape cache mutation count mid-render. The ShapeLayout and shape_gen locals are now mutable so the snapshot can be updated after the loop, reflecting that the layout pointer was safely dereferenced before any eviction could have freed the underlying glyph vectors.
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Inline comments:
In `@indra/llrender/llfonttextcache.h`:
- Line 104: Resolve the merge conflicts in the public header by removing all
conflict markers, including the second conflict near the later metadata fields.
Preserve the metadata-only mRecordedLength branch and remove the mRecordedText
branch so the header compiles cleanly.
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indra/llrender/llfonttextcache.h
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Description
Fixes two debug assertion crashes that occurred on the login screen,
both rooted in the new HarfBuzz shaping and font text cache systems.
2 crashes fixed.
llrender/llfonttextcache.cpp(242): ASSERT (sameTextAsRecorded(text))LLLineEditor's password masking temporarily swapsmTextin-placewith a bullet string (
••••••••) for rendering, then restores it.The font cache had already fingerprinted the real password text, so
when the bullet string was rendered through the same cache object the
fingerprint check failed.
Fix: reset the three font buffer caches (pre-selection, selection,
post-selection) immediately before and after the
mDrawAsterixestextswap, so neither the bullet render nor the subsequent real-text width
measurement inherits a stale fingerprint from the other.
llrender/llfontgl.cpp(996): ASSERT (layout.mutation_snapshot == ALFontShaping::cacheMutationCount())The
ShapeLayoutbuilt at the start ofrenderBytessnapshots theshape cache mutation count and holds a raw pointer into the shape LRU.
During the render loop, rasterizing a cold glyph can evict an atlas
sheet, dropping an
LLPointer<LLFontFreetype>and calling~LLFontFreetype, which callsALFontShaping::clearCacheForFaceandbumps the mutation count. The post-loop assert then fires even though
the layout pointer was safely dereferenced before any eviction occurred.
Fix: remove
constfrom theShapeLayoutandshape_genlocals sothe mutation snapshot can be updated after the loop completes,
accurately reflecting that no unsafe dereference took place.
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