Rollup merge of #79298 - lcnr:new-elysium, r=matthewjasper

correctly deal with late-bound lifetimes in anon consts

adds support for using late bound lifetimes of the parent context in anon consts.
```rust
#![feature(const_generics)]
const fn inner<'a>() -> usize where &'a (): Sized { 3 }

fn test<'a>() {
    let _: [u8; inner::<'a>()];
}
```
The lifetime `'a` is late bound in `test` so it's not included in its generics but is instead dealt with separately in borrowck.
This didn't previously work for anon consts as they have to use the late bound lifetimes of their parent which has
to be explicitly handled.

r? ```@matthewjasper``` cc ```@varkor``` ```@eddyb```
This commit is contained in:
Mara Bos
2021-01-17 12:24:39 +00:00
committed by GitHub
6 changed files with 71 additions and 8 deletions

View File

@@ -788,13 +788,13 @@ fn for_each_late_bound_region_defined_on<'tcx>(
fn_def_id: DefId,
mut f: impl FnMut(ty::Region<'tcx>),
) {
if let Some(late_bounds) = tcx.is_late_bound_map(fn_def_id.expect_local()) {
for late_bound in late_bounds.iter() {
let hir_id = HirId { owner: fn_def_id.expect_local(), local_id: *late_bound };
if let Some((owner, late_bounds)) = tcx.is_late_bound_map(fn_def_id.expect_local()) {
for &late_bound in late_bounds.iter() {
let hir_id = HirId { owner, local_id: late_bound };
let name = tcx.hir().name(hir_id);
let region_def_id = tcx.hir().local_def_id(hir_id);
let liberated_region = tcx.mk_region(ty::ReFree(ty::FreeRegion {
scope: fn_def_id,
scope: owner.to_def_id(),
bound_region: ty::BoundRegionKind::BrNamed(region_def_id.to_def_id(), name),
}));
f(liberated_region);