Cast IMPs to the correct signature before calling - #418
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| NewAutoreleasePool = reinterpret_cast<NewAutoreleasePoolIMP>( | ||
| class_getMethodImplementation(object_getClass(AutoreleasePool), | ||
| SELECTOR(new))); |
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Can we consolidate the casts with something like:
auto storeSelector = [](auto &target, IMP imp)
{
target = reinterpret_cast<std::remove_reference_t<decltype(target)>>(imp);
};| // `.cxx_destruct` method may deallocate the class. | ||
| Class currentClass = cls; | ||
| cls = cls->super_class; | ||
| if (currentClass->cxx_destruct) |
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We should probably change the type of these from IMP and do the cast when we set them.
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updated |
davidchisnall
approved these changes
Aug 25, 2026
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Please can you squash for merging? |
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Done. I don't think I have permissions to merge PRs myself. |
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This PR ensures we do not call any raw IMP function pointers without casting them to the correct type first.
Calling a funtion pointer with a mismatching signature is technically UB I believe but tends to work just fine on many native platforms.
With WebAssembly, this is a problem however, because WASM indirect calls require an exact signature match. This can cause runtime failures.