[Runtime] Avoid +class overrides when initializing an ObjC class. #24618
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swift_getInitializedObjCClass called [c class] to trigger class initialization, and returned the value. This wreaked havoc when the class in question overrides +class. Instead, ignore the return value and return c. Switch from +class to +self, which is much less likely to be overridden. Calling an overridden method could have performance downsides or even cause unwanted side effects. rdar://problem/49853091
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@swift-ci please test |
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I think it's possible to write a terrible test case for this that would fail the old way. |
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I think you're right! |
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That does indeed trigger a failure with the old code. New code works. |
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@swift-ci please test |
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| // RUN: mkdir -p %t | |||
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Nitpick: %empty-directory(%t) will also clear out any contents left over from the last run.
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Thanks. We have a bunch of tests with each one, and I happened to crib from one with mkdir. Seems better to do it with empty-directory though.
rdar://problem/49853091
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swift_getInitializedObjCClass called [c class] to trigger class initialization, and returned the value. This wreaked havoc when the class in question overrides +class. Instead, ignore the return value and return c. Switch from +class to +self, which is much less likely to be overridden. Calling an overridden method could have performance downsides or even cause unwanted side effects.
rdar://problem/49853091