rust-lang/rust
1
0
Fork 0
Code Issues Pull Requests Actions 1 Packages Projects Releases Wiki Activity

remove some trait solver helpers

Browse Source 
they add more complexity then they are worth. It's confusing
which of these helpers should be used in which context.
This commit is contained in:
lcnr
2023-03-14 14:19:06 +01:00
parent 84c47b8279
commit 791ce0b7b5
31 changed files with 199 additions and 289 deletions
Download Patch File Download Diff File Expand all files Collapse all files

44
compiler/rustc_trait_selection/src/traits/select/confirmation.rs
View File

@@ -18,7 +18,7 @@ use rustc_session::config::TraitSolver;
use rustc_span::def_id::DefId;
use crate::traits::project::{normalize_with_depth, normalize_with_depth_to};
use crate::traits::util::{self, closure_trait_ref_and_return_type, predicate_for_trait_def};
use crate::traits::util::{self, closure_trait_ref_and_return_type};
use crate::traits::vtable::{
count_own_vtable_entries, prepare_vtable_segments, vtable_trait_first_method_offset,
VtblSegment,
@@ -253,15 +253,13 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
};
let cause = obligation.derived_cause(BuiltinDerivedObligation);
ensure_sufficient_stack(|| {
self.collect_predicates_for_types(
obligation.param_env,
cause,
obligation.recursion_depth + 1,
trait_def,
nested,
)
})
self.collect_predicates_for_types(
obligation.param_env,
cause,
obligation.recursion_depth + 1,
trait_def,
nested,
)
} else {
vec![]
};
@@ -1118,14 +1116,11 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
nested.extend(obligations);
// Construct the nested `TailField<T>: Unsize<TailField<U>>` predicate.
nested.push(predicate_for_trait_def(
let tail_unsize_obligation = obligation.with(
tcx,
obligation.param_env,
obligation.cause.clone(),
obligation.predicate.def_id(),
obligation.recursion_depth + 1,
[source_tail, target_tail],
));
tcx.mk_trait_ref(obligation.predicate.def_id(), [source_tail, target_tail]),
);
nested.push(tail_unsize_obligation);
}
// `(.., T)` -> `(.., U)`
@@ -1147,17 +1142,10 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
.map_err(|_| Unimplemented)?;
nested.extend(obligations);
// Construct the nested `T: Unsize<U>` predicate.
nested.push(ensure_sufficient_stack(|| {
predicate_for_trait_def(
tcx,
obligation.param_env,
obligation.cause.clone(),
obligation.predicate.def_id(),
obligation.recursion_depth + 1,
[a_last, b_last],
)
}));
// Add a nested `T: Unsize<U>` predicate.
let last_unsize_obligation = obligation
.with(tcx, tcx.mk_trait_ref(obligation.predicate.def_id(), [a_last, b_last]));
nested.push(last_unsize_obligation);
}
_ => bug!("source: {source}, target: {target}"),