bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Add traits::fully_solve_obligation that acts like traits::fully_normalize

Browse source 
It spawns up a trait engine, registers the single obligation, then fully
solves it
This commit is contained in:
Michael Goulet 2022-08-02 06:02:04 +00:00
parent 3e48434cc7
commit fe894756f8
10 changed files with 78 additions and 97 deletions
Download patch file Download diff file Expand all files Collapse all files

43
compiler/rustc_trait_selection/src/traits/mod.rs
View file

@ -30,6 +30,7 @@ use rustc_errors::ErrorGuaranteed;
use rustc_hir as hir;
use rustc_hir::def_id::DefId;
use rustc_hir::lang_items::LangItem;
use rustc_infer::traits::TraitEngineExt as _;
use rustc_middle::ty::fold::TypeFoldable;
use rustc_middle::ty::subst::{InternalSubsts, SubstsRef};
use rustc_middle::ty::visit::TypeVisitable;
@ -161,22 +162,20 @@ pub fn type_known_to_meet_bound_modulo_regions<'a, 'tcx>(
// this function's result remains infallible, we must confirm
// that guess. While imperfect, I believe this is sound.
// The handling of regions in this area of the code is terrible,
// see issue #29149. We should be able to improve on this with
// NLL.
let mut fulfill_cx = <dyn TraitEngine<'tcx>>::new(infcx.tcx);
// We can use a dummy node-id here because we won't pay any mind
// to region obligations that arise (there shouldn't really be any
// anyhow).
let cause = ObligationCause::misc(span, hir::CRATE_HIR_ID);
fulfill_cx.register_bound(infcx, param_env, ty, def_id, cause);
// The handling of regions in this area of the code is terrible,
// see issue #29149. We should be able to improve on this with
// NLL.
let errors = fully_solve_bound(infcx, cause, param_env, ty, def_id);
// Note: we only assume something is `Copy` if we can
// *definitively* show that it implements `Copy`. Otherwise,
// assume it is move; linear is always ok.
match fulfill_cx.select_all_or_error(infcx).as_slice() {
match &errors[..] {
[] => {
debug!(
"type_known_to_meet_bound_modulo_regions: ty={:?} bound={} success",
@ -413,6 +412,36 @@ where
Ok(resolved_value)
}
pub fn fully_solve_obligation<'a, 'tcx>(
infcx: &InferCtxt<'a, 'tcx>,
obligation: PredicateObligation<'tcx>,
) -> Vec<FulfillmentError<'tcx>> {
let mut engine = <dyn TraitEngine<'tcx>>::new(infcx.tcx);
engine.register_predicate_obligation(infcx, obligation);
engine.select_all_or_error(infcx)
}
pub fn fully_solve_obligations<'a, 'tcx>(
infcx: &InferCtxt<'a, 'tcx>,
obligations: impl IntoIterator<Item = PredicateObligation<'tcx>>,
) -> Vec<FulfillmentError<'tcx>> {
let mut engine = <dyn TraitEngine<'tcx>>::new(infcx.tcx);
engine.register_predicate_obligations(infcx, obligations);
engine.select_all_or_error(infcx)
}
pub fn fully_solve_bound<'a, 'tcx>(
infcx: &InferCtxt<'a, 'tcx>,
cause: ObligationCause<'tcx>,
param_env: ty::ParamEnv<'tcx>,
ty: Ty<'tcx>,
bound: DefId,
) -> Vec<FulfillmentError<'tcx>> {
let mut engine = <dyn TraitEngine<'tcx>>::new(infcx.tcx);
engine.register_bound(infcx, param_env, ty, bound, cause);
engine.select_all_or_error(infcx)
}
/// Normalizes the predicates and checks whether they hold in an empty environment. If this
/// returns true, then either normalize encountered an error or one of the predicates did not
/// hold. Used when creating vtables to check for unsatisfiable methods.