iOS: bound safe_area()'s boot-path dispatch_sync to avoid a launch deadlock - #74
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…adlock Mob.Screen.init/1 calls safe_area() synchronously before the first screen mounts. A plain dispatch_sync to the main queue there is a deadlock risk if the main thread hasn't reached an idle run-loop tick yet — observed via a device-family/compatibility-mode boot hang on iPad. Switch to dispatch_async + a bounded semaphore wait, falling back to zero insets on timeout, and mark the NIF dirty (IO-bound) so a slow main thread can no longer stall a regular BEAM scheduler either. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
…k screen If BEAM boot doesn't produce a first screen within 15s, surface an explicit "Startup Error" state instead of leaving the black startup spinner running forever. An indefinite spinner and a persistent error look identical to "frozen" from the outside — this makes any future boot-path stall diagnosable (and visibly not "blank") rather than ambiguous. Follow-up to the safe_area() dispatch_sync fix: that closed the one known boot-path deadlock, but a second App Store review on the fixed build still reported a black/blank launch on iPad. Root-cause without physical iPad hardware isn't possible from here, so this is a defensive net for whatever is still stalling boot on that device/OS combination, verified not to false-positive on a normal boot (simulator, both iPhone and iPad). Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
If the watchdog fires, show "Version <CFBundleShortVersionString> (<CFBundleVersion>)" alongside the error text — a cheap way to confirm whoever sees it (us, a tester, a reviewer) is actually looking at the build they think they are, rather than a stale cached copy. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
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GenericJam added a commit
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Aug 28, 2026
…eadlock fix Carries three merged changes since 0.7.31: - #94 intrinsic Sheet detents ([:content] / [{:content, max_height: n}]) with canonical validation through Mob.UI.normalize_sheet_detents!/1 re-applied at the renderer boundary, iOS content measurement with capping, internal scrolling and geometry re-clamping, composite Box accessibility (label, explicit button role, disabled semantics), and Sheet in both platform tag manifests. - #74 the iOS launch deadlock behind an App Store rejection — safe_area()'s unbounded dispatch_sync on the boot path could block the BEAM thread forever so the app never finished launching. - #78 iOS glass tint from the node background, and left-aligned fill_width rows. The changelog records two known limitations rather than leaving them to be discovered: a scrollable child inside a content detent expands instead of scrolling independently (it reports intrinsic height), and a content sheet presents at :medium for one frame before resizing, since content height is only knowable after presentation. Preflight: mix format, credo --strict, compile --warnings-as-errors, 1119 tests, git diff --check, and the native frame-registry harness all clean. The Sheet work was additionally adversarially reviewed and device-verified on an iPhone 17 Pro simulator (hug, cap, internal scroll, safe-area clearance) and the Box/Android half on a physical Moto G. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
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Summary
Mob.Screen.init/1callssafe_area()synchronously before the first screen ever mounts. A plaindispatch_syncto the main queue there is a deadlock risk if the main thread hasn't reached an idle run-loop tick yet by that point.sloppy_joe: "the app kept loading indefinitely on launch," reproduced by the reviewer on an iPad Air 11-inch (M3) / iPadOS 26.5.2. The BEAM boot thread was blocking forever inside this NIF call, so the app never finished launching.dispatch_async+ a semaphore bounded to 2s, falling back to zero insets on timeout — a screen with wrong insets once is a far smaller bug than an app that never boots. Also mark the NIF dirty (ERL_NIF_DIRTY_JOB_IO_BOUND) so a slow main thread can no longer stall a regular BEAM scheduler either.Test plan
xcrun clang-format --dry-run -Werror ios/mob_nif.m— cleansloppy_joe(pointedmob_dirat this branch): app boots correctly on both iPhone and iPad simulators, before and after forcingUIDeviceFamily=[1]on the installed bundle (mirroring the App-Store-only device-family patch)UIDeviceFamily=[1]app)🤖 Generated with Claude Code