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mayoff/unowned-safety-dance.swift

Created February 23, 2019 03:00
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test Swift unowned safety
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unowned-safety-dance.swift
class MyObject { }
var o = MyObject()
print("strong o = \(o)")
unowned let u = o
print("unowned u = \(u)")
o = MyObject()
print("new strong o = \(o)")
print("old unowned u = \(u)")
@hamishknight
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@robertmryan Ah interesting! Sorry, I missed that part in your original post. Upon re-inspection, you get the same behaviour in 4.2 and 5.0 – it just appears to be sometimes hitting the runtime error and sometimes crashing with EXC_BAD_ACCESS. Digging a bit further, when running with an assert Swift runtime it trips an assertion.

Filed a bug: SR-9999.

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