fix(metal): NSString double-free on autorelease pool drain #39
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Problem: - NSString() used stringWithUTF8String: which returns autoreleased object - Callers then called Release() on these objects - When autorelease pool drained, it released already-freed objects - Caused intermittent panics in CreateRenderPipeline on macOS CI Root cause: - stringWithUTF8String: returns +0 autoreleased object (owned by pool) - Manual Release() decrements retain count below 0 - pool.Drain() tries to release invalid object = crash Fix: - Use alloc/initWithUTF8String: instead of stringWithUTF8String: - Returns +1 retained object owned by caller - Caller's Release() correctly decrements to 0 and frees - pool.Drain() has nothing extra to release Reference: Objective-C Memory Management Rules - alloc/init returns +1 retained - convenience methods (stringWith...) return +0 autoreleased
kolkov
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Jan 5, 2026
- Document NSString double-free fix (#39) - Update version status to v0.9.2
kolkov
added a commit
that referenced
this pull request
Jan 5, 2026
- Document NSString double-free fix (#39) - Update version status to v0.9.2
This was referenced Jan 5, 2026
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Problem
Intermittent panics in
CreateRenderPipelineon macOS CI:Root Cause
NSString()function usedstringWithUTF8String:which returns an autoreleased object (+0 retain count, owned by autorelease pool).Callers then called
Release()on these objects:Release(label)decrements retain count below 0 (invalid)pool.Drain()tries to release already-freed objectFix
Use
alloc/initWithUTF8String:instead ofstringWithUTF8String::Release()correctly decrements to 0 and freespool.Drain()has nothing extra to releaseObjective-C Memory Management Rules
alloc,new,copy,mutableCopystringWith..., convenience methodsTest Plan
go build ./hal/metal/...— Passgolangci-lint run ./hal/metal/...— 0 issues