squiid/rust
1
0
Fork 0
Code Issues Pull requests Projects Activity

Sync from rust 9863bf51a5

Browse source
This commit is contained in:
bjorn3 2021-08-25 13:05:20 +02:00
commit f865bbbecf
1 changed files with 3 additions and 14 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

17
src/unsize.rs
View file

@ -31,21 +31,10 @@ pub(crate) fn unsized_info<'tcx>(
if data_a.principal_def_id() == data_b.principal_def_id() {
return old_info;
}
// trait upcasting coercion
// if both of the two `principal`s are `None`, this function would have returned early above.
// and if one of the two `principal`s is `None`, typechecking would have rejected this case.
let principal_a = data_a
.principal()
.expect("unsized_info: missing principal trait for trait upcasting coercion");
let principal_b = data_b
.principal()
.expect("unsized_info: missing principal trait for trait upcasting coercion");
let vptr_entry_idx = fx.tcx.vtable_trait_upcasting_coercion_new_vptr_slot((
principal_a.with_self_ty(fx.tcx, source),
principal_b.with_self_ty(fx.tcx, source),
));
let vptr_entry_idx =
fx.tcx.vtable_trait_upcasting_coercion_new_vptr_slot((source, target));
if let Some(entry_idx) = vptr_entry_idx {
let entry_idx = u32::try_from(entry_idx).unwrap();