# Binaries produced by Swift 5.2 betas crash while mapping optionals of Obj-C types annotated with objc\_runtmie\_name

**URL:** <https://forums.swift.org/t/binaries-produced-by-swift-5-2-betas-crash-while-mapping-optionals-of-obj-c-types-annotated-with-objc-runtmie-name/34334>\
**Category:** Using Swift\
**Tags:** bug, objective-c, regression\
**Created:** [March 5, 2020, 8:10am UTC](https://forums.swift.org/t/binaries-produced-by-swift-5-2-betas-crash-while-mapping-optionals-of-obj-c-types-annotated-with-objc-runtmie-name/34334 "2020-03-05T08:10:01Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![kasyanov](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/kasyanov/32/10791_2.png) [@kasyanov](https://forums.swift.org/u/kasyanov)\
**Post date:** [March 5, 2020, 8:10am UTC](https://forums.swift.org/t/binaries-produced-by-swift-5-2-betas-crash-while-mapping-optionals-of-obj-c-types-annotated-with-objc-runtmie-name/34334/1 "2020-03-05T08:10:01Z")

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Hi folks,

here's the bug: [[SR-12169] Using `objc_runtime_name` causes Swift 5.2 binary segmentation fault · Issue #54594 · apple/swift · GitHub](https://bugs.swift.org/browse/SR-12169).

I'm a bit worried it won't get addressed before Xcode 11.4 GM lands, that's why I'm posting here. I'd like to look into it myself, any pointers appreciated.

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**Author:** ![Joe\_Groff](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/joe_groff/32/1929_2.png) [@Joe\_Groff](https://forums.swift.org/u/Joe_Groff)\
**Post date:** [March 5, 2020, 10:23pm UTC](https://forums.swift.org/t/binaries-produced-by-swift-5-2-betas-crash-while-mapping-optionals-of-obj-c-types-annotated-with-objc-runtmie-name/34334/2 "2020-03-05T22:23:29Z")

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Here is a fix: [IRGen: Generate runtime type manglings using ObjC runtime names. by jckarter · Pull Request #30250 · apple/swift · GitHub](https://github.com/apple/swift/pull/30250/files)