mirror of
https://github.com/rust-lang/rust.git
synced 2025-10-03 02:40:40 +00:00

MIR-build: No longer emit assumes in enum-as casting This just uses the `valid_range` from the backend, so it's duplicating the range metadata that now we include on parameters and loads, and thus no longer seems to be useful -- notably there's no codegen test failures from removing it. (Because it's using data from the same source as the backend annotations, it doesn't do anything to mitigate things like rust-lang/rust#144388 where the range in the layout is more permissive than the actual possible discriminants. A variant of this that actually checked the discriminants more specifically might be useful, so could potentially be added in future, but I don't think the *current* checks are actually providing value.) r? mir Randomly turns out that this Fixes https://github.com/rust-lang/rust/issues/121097