mikros/rust
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Rollup merge of #120155 - compiler-errors:no-erased-when-promoting, r=aliemjay

Browse Source 
Don't use `ReErased` to detect type test promotion failed

Using `ReErased` here is convenient because it implicitly stores the state that we are explicitly recording with the `failed` variable now, but I also think it adds a tiny bit of complexity that is not worth it.

r? `@aliemjay`
This commit is contained in:
Matthias Krüger 2024-01-20 09:37:30 +01:00 committed by GitHub
commit bb816e67b4
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
1 changed files with 9 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
compiler/rustc_borrowck/src/region_infer/mod.rs
View File

@ -18,7 +18,7 @@
};
use rustc_middle::traits::ObligationCause;
use rustc_middle::traits::ObligationCauseCode;
use rustc_middle::ty::{self, RegionVid, Ty, TyCtxt, TypeFoldable, TypeVisitableExt};
use rustc_middle::ty::{self, RegionVid, Ty, TyCtxt, TypeFoldable};
use rustc_mir_dataflow::points::DenseLocationMap;
use rustc_span::Span;
@ -1145,6 +1145,7 @@ fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> {
}
let ty = ty.fold_with(&mut OpaqueFolder { tcx });
let mut failed = false;
let ty = tcx.fold_regions(ty, |r, _depth| {
let r_vid = self.to_region_vid(r);
@ -1160,15 +1161,18 @@ fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> {
.filter(|&u_r| !self.universal_regions.is_local_free_region(u_r))
.find(|&u_r| self.eval_equal(u_r, r_vid))
.map(|u_r| ty::Region::new_var(tcx, u_r))
// In the case of a failure, use `ReErased`. We will eventually
// return `None` in this case.
.unwrap_or(tcx.lifetimes.re_erased)
// In case we could not find a named region to map to,
// we will return `None` below.
.unwrap_or_else(|| {
failed = true;
r
})
});
debug!("try_promote_type_test_subject: folded ty = {:?}", ty);
// This will be true if we failed to promote some region.
if ty.has_erased_regions() {
if failed {
return None;
}