fix RCTImageManager crash#2
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SzymczakJ merged 3 commits intoJun 18, 2026
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Backport of upstream PR react#55135 ("fix rctimage observer crash when unloading with events in-flight"). Convert ImageResponseObserverCoordinator's observers from raw pointers to std::shared_ptr<const ImageResponseObserver> so an observer cannot dangle while an image event is in flight (the documented react#55135 crash in nativeImageResponseProgress). RCTImageComponentView now holds its proxy as a shared_ptr and passes it directly (a final ImageResponseObserver subclass converts implicitly to shared_ptr<const ImageResponseObserver>). Also fix an over-removal bug in removeObserver: erase(position, end()) removed every observer from the match onward, which could prematurely empty observers_ and trigger an unwanted cancelRequest_(). Use erase(position) to remove only the single matched observer, matching the add/remove balance the comment describes. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
…crash `loaderRequest.cancellationBlock` can be nil (a loader that returns no cancellation block, or a request that has already completed). The captured `sharedCancelationFunction` invoked it unconditionally, so when a cancel is triggered during view recycling (RCTImageComponentView::prepareForRecycle → _setStateAndResubscribeImageResponseObserver → removeObserver → cancelRequest_()), a nil block was called. Invoking a nil Objective-C block dereferences `block->invoke` at offset 0x10 → EXC_BAD_ACCESS / KERN_INVALID_ADDRESS at 0x10. Nil-guard the captured block so the cancel is a no-op when there is nothing to cancel. This is Discord-specific hardening on top of the upstream observer-lifetime fix (react#55135, ported in the preceding commit) and is the likely direct cause of the reported crash. Fixes DISCORD-IOS-M4EH Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
WoLewicki
approved these changes
Jun 17, 2026
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Possibly fixes: https://discord.sentry.io/issues/7451653844/?project=230973&query=&referrer=issue-stream&sort=freq - Asana
majority of changes are taken from react#55135 which fixes similar bug upstream. Rest is additional hardening in RCTImageManager to fix all the edge cases.