Don't use __derived_enum_equals for a resilient synthesized '==' #18508
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(or __derived_struct_equals) We want to make sure that if someone replaces the synthesized implementation with a handwritten one, it doesn't change the ABI. The simplest way to do that is to not use this clever workaround. https://bugs.swift.org/browse/SR-8294
graydon
approved these changes
Aug 4, 2018
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(@jrose-apple btw, thanks for doing this!) |
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@jrose-apple Ok, I guess ideally, the synthesized witness would be private, and we would support 'opaque witnesses'; then it wouldn't get a symbol at all. Note that a top-level operator has a different mangling than a static method operator too... |
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It's not about the witness case; it's about direct calls not backwards-deploying. I'm not sure what to do about the top-level thing, but at least there's not really a reason to use a top-level operator with a concrete type anymore. |
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(or __derived_struct_equals)
We want to make sure that if someone replaces the synthesized implementation with a handwritten one, it doesn't change the ABI. The simplest way to do that is to not use this clever workaround from #8735.
SR-8294 / rdar://problem/42302849