6bcdf8aa74
Allow transmutes between the same types after erasing lifetimes r? ````@compiler-errors```` on the impl fixes #101081 See discussion in the issue and at https://rust-lang.zulipchat.com/#narrow/stream/326866-t-types.2Fnominated/topic/.23101081.3A.20Regression.20transmuting.20.60RwLockReadGuard.3CT.3A.20.3FSized.3E.E2.80.A6 I think this may need lang team signoff as its implications may go beyond the jurisdiction of T-types I'll write up a proper summary later
For high-level intro to how type checking works in rustc, see the type checking chapter of the rustc dev guide.