bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Auto merge of #109119 - lcnr:trait-system-cleanup, r=compiler-errors

Browse source 
a general type system cleanup

removes the helper functions `traits::fully_solve_X` as they add more complexity then they are worth. It's confusing which of these helpers should be used in which context.

changes the way we deal with overflow to always add depth in `evaluate_predicates_recursively`. It may make sense to actually fully transition to not have `recursion_depth` on obligations but that's probably a bit too much for this PR.

also removes some other small - and imo unnecessary - helpers.

r? types
This commit is contained in:
bors 2023-03-22 05:33:18 +00:00
commit 9bdb4881c7
39 changed files with 259 additions and 385 deletions
Download patch file Download diff file Expand all files Collapse all files

42
compiler/rustc_hir_analysis/src/hir_wf_check.rs
View file

@ -7,7 +7,7 @@ use rustc_infer::traits::{ObligationCause, WellFormedLoc};
use rustc_middle::ty::query::Providers;
use rustc_middle::ty::{self, Region, TyCtxt, TypeFoldable, TypeFolder};
use rustc_span::def_id::LocalDefId;
use rustc_trait_selection::traits;
use rustc_trait_selection::traits::{self, ObligationCtxt};
pub fn provide(providers: &mut Providers) {
*providers = Providers { diagnostic_hir_wf_check, ..*providers };
@ -66,35 +66,35 @@ fn diagnostic_hir_wf_check<'tcx>(
impl<'tcx> Visitor<'tcx> for HirWfCheck<'tcx> {
fn visit_ty(&mut self, ty: &'tcx hir::Ty<'tcx>) {
let infcx = self.tcx.infer_ctxt().build();
let ocx = ObligationCtxt::new(&infcx);
let tcx_ty = self.icx.to_ty(ty).fold_with(&mut EraseAllBoundRegions { tcx: self.tcx });
let cause = traits::ObligationCause::new(
ty.span,
self.def_id,
traits::ObligationCauseCode::WellFormed(None),
);
let errors = traits::fully_solve_obligation(
&infcx,
traits::Obligation::new(
self.tcx,
cause,
self.param_env,
ty::Binder::dummy(ty::PredicateKind::WellFormed(tcx_ty.into())),
),
);
if !errors.is_empty() {
debug!("Wf-check got errors for {:?}: {:?}", ty, errors);
for error in errors {
if error.obligation.predicate == self.predicate {
// Save the cause from the greatest depth - this corresponds
// to picking more-specific types (e.g. `MyStruct<u8>`)
// over less-specific types (e.g. `Option<MyStruct<u8>>`)
if self.depth >= self.cause_depth {
self.cause = Some(error.obligation.cause);
self.cause_depth = self.depth
}
ocx.register_obligation(traits::Obligation::new(
self.tcx,
cause,
self.param_env,
ty::PredicateKind::WellFormed(tcx_ty.into()),
));
for error in ocx.select_all_or_error() {
debug!("Wf-check got error for {:?}: {:?}", ty, error);
if error.obligation.predicate == self.predicate {
// Save the cause from the greatest depth - this corresponds
// to picking more-specific types (e.g. `MyStruct<u8>`)
// over less-specific types (e.g. `Option<MyStruct<u8>>`)
if self.depth >= self.cause_depth {
self.cause = Some(error.obligation.cause);
self.cause_depth = self.depth
}
}
}
self.depth += 1;
intravisit::walk_ty(self, ty);
self.depth -= 1;