5899a80ae6
Correct codegen of `ConstValue::Indirect` scalar and scalar pair This concerns 3 tricky cases with `ConstValue::Indirect`: - if we want a non-pointer scalar; - if we have non-zero offset; - if offset points to uninit memory => generate `poison` instead of an ICE. This case could happen in unreachable code, trying to extract a field from the wrong variant. Those cases are not currently emitted by the compiler, but are exercised by https://github.com/rust-lang/rust/pull/116012.
Please read the rustc-dev-guide chapter on Backend Agnostic Codegen.