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propagate the compare_ty fn further up

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This commit is contained in:
Niko Matsakis 2018-09-17 13:44:20 -04:00
parent 13d579bd62
commit 4b193cb92a
1 changed files with 17 additions and 18 deletions
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35
src/librustc/infer/outlives/verify.rs
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@ -102,23 +102,15 @@ impl<'cx, 'gcx, 'tcx> VerifyBoundCx<'cx, 'gcx, 'tcx> {
self.declared_projection_bounds_from_trait(projection_ty)
}
pub fn projection_bound(
&self,
projection_ty: ty::ProjectionTy<'tcx>,
) -> VerifyBound<'tcx> {
debug!(
"projection_bound(projection_ty={:?})",
projection_ty
);
pub fn projection_bound(&self, projection_ty: ty::ProjectionTy<'tcx>) -> VerifyBound<'tcx> {
debug!("projection_bound(projection_ty={:?})", projection_ty);
// Search the env for where clauses like `P: 'a`.
let mut declared_bounds =
self.declared_generic_bounds_from_env(GenericKind::Projection(projection_ty));
// Extend with bounds that we can find from the trait.
declared_bounds.extend(
self.projection_declared_bounds_from_trait(projection_ty)
);
declared_bounds.extend(self.projection_declared_bounds_from_trait(projection_ty));
debug!("projection_bound: declared_bounds = {:?}", declared_bounds);
@ -158,6 +150,14 @@ impl<'cx, 'gcx, 'tcx> VerifyBoundCx<'cx, 'gcx, 'tcx> {
fn declared_generic_bounds_from_env(
&self,
generic: GenericKind<'tcx>,
) -> Vec<ty::Region<'tcx>> {
let generic_ty = generic.to_ty(self.tcx);
self.declared_generic_bounds_from_env_with_compare_fn(|ty| ty == generic_ty)
}
fn declared_generic_bounds_from_env_with_compare_fn(
&self,
compare_ty: impl Fn(Ty<'tcx>) -> bool,
) -> Vec<ty::Region<'tcx>> {
let tcx = self.tcx;
@ -167,12 +167,8 @@ impl<'cx, 'gcx, 'tcx> VerifyBoundCx<'cx, 'gcx, 'tcx> {
// dubious for projections, but it will work for simple cases
// like `T` and `T::Item`. It may not work as well for things
// like `<T as Foo<'a>>::Item`.
let generic_ty = generic.to_ty(tcx);
let c_b = self.param_env.caller_bounds;
let mut param_bounds = self.collect_outlives_from_predicate_list(
|ty| ty == generic_ty,
c_b,
);
let mut param_bounds = self.collect_outlives_from_predicate_list(&compare_ty, c_b);
// Next, collect regions we scraped from the well-formedness
// constraints in the fn signature. To do that, we walk the list
@ -186,8 +182,11 @@ impl<'cx, 'gcx, 'tcx> VerifyBoundCx<'cx, 'gcx, 'tcx> {
// well-formed, then, A must be lower-generic by `'a`, but we
// don't know that this holds from first principles.
for &(r, p) in self.region_bound_pairs {
debug!("generic={:?} p={:?}", generic, p);
if generic == p {
debug!(
"declared_generic_bounds_from_env_with_compare_fn: region_bound_pair = {:?}",
(r, p)
);
if compare_ty(p.to_ty(tcx)) {
param_bounds.push(r);
}
}