fix: SIGBUS on Apple Silicon — ObjC block PAC re-signing (v0.19.2)#90
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fix: SIGBUS on Apple Silicon — ObjC block PAC re-signing (v0.19.2)#90
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- core/backend_test.go: backend registry, provider selection tests - hal/backends_test.go: factory pattern, backend enumeration tests - hal/dx12/convert_test.go: DX12 format/blend conversion tests - hal/gles/convert_test.go: expanded GLES format conversion tests - hal/noop/noop_test.go: expanded noop backend tests with error handling - hal/software/software_test.go: expanded software backend tests - hal/vulkan/convert_test.go: expanded Vulkan format conversion tests
…ocks ObjC blocks were constructed with _NSConcreteStackBlock + flags=0, but allocated on the Go heap. When Metal calls Block_copy() on these blocks during addCompletedHandler:, ARM64e PAC re-signs the invoke pointer. Our ffi.NewCallback pointers are unsigned, so authentication fails, producing a corrupted pointer that causes SIGBUS when Metal's completion queue invokes the callback. Switch to _NSConcreteGlobalBlock + BLOCK_IS_GLOBAL (1<<28), which makes Block_copy() a complete no-op (no memmove, no PAC re-signing). Add blockPinRegistry (sync.Map) to keep block literals alive since global blocks are not copied by Metal. Remove stale runtime.KeepAlive(uintptr) calls that were no-ops (GC doesn't track uintptr as roots). Fixes #89
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Summary
_NSConcreteStackBlockon Go heap → PAC re-signing failure). Switch to_NSConcreteGlobalBlock+BLOCK_IS_GLOBALflag, addblockPinRegistryfor GC safety, remove staleruntime.KeepAlive(uintptr)no-ops.codecov.ymlFixes #89
Test plan
GOOS=darwin GOARCH=arm64cross-compile cleanGOOS=darwin GOARCH=amd64cross-compile cleango test ./...)golangci-lint run)