Auto merge of - matthiaskrgr:rollup-75i6oz5, r=matthiaskrgr

Rollup of 4 pull requests

Successful merges:

 -  (Update browser-ui-test version to 0.8.2)
 -  (Make negative coherence work when there's impl negative on super predicates)
 -  (Refactor: remove an unnecessary pattern for ignoring all parts)
 -  (update Miri)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
This commit is contained in:
bors 2022-03-18 05:26:14 +00:00
commit 691d1c1e12
10 changed files with 100 additions and 47 deletions
compiler
rustc_middle/src/ty
rustc_resolve/src
rustc_trait_selection/src/traits
src

View file

@ -748,6 +748,13 @@ pub struct TraitPredicate<'tcx> {
pub constness: BoundConstness,
/// If polarity is Positive: we are proving that the trait is implemented.
///
/// If polarity is Negative: we are proving that a negative impl of this trait
/// exists. (Note that coherence also checks whether negative impls of supertraits
/// exist via a series of predicates.)
///
/// If polarity is Reserved: that's a bug.
pub polarity: ImplPolarity,
}

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@ -1129,7 +1129,7 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
}
for param in &generics.params {
if let GenericParamKind::Lifetime { .. } = param.kind {
if let GenericParamKind::Lifetime = param.kind {
continue;
}

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@ -17,8 +17,8 @@ use crate::traits::{
use rustc_errors::Diagnostic;
use rustc_hir::def_id::{DefId, LOCAL_CRATE};
use rustc_hir::CRATE_HIR_ID;
use rustc_infer::infer::TyCtxtInferExt;
use rustc_infer::traits::TraitEngine;
use rustc_infer::infer::{InferCtxt, TyCtxtInferExt};
use rustc_infer::traits::{util, TraitEngine};
use rustc_middle::traits::specialization_graph::OverlapMode;
use rustc_middle::ty::fast_reject::{self, TreatParams};
use rustc_middle::ty::fold::TypeFoldable;
@ -353,6 +353,8 @@ fn negative_impl<'cx, 'tcx>(
})
}
/// Try to prove that a negative impl exist for the given obligation and their super predicates.
#[instrument(level = "debug", skip(selcx))]
fn negative_impl_exists<'cx, 'tcx>(
selcx: &SelectionContext<'cx, 'tcx>,
param_env: ty::ParamEnv<'tcx>,
@ -360,42 +362,66 @@ fn negative_impl_exists<'cx, 'tcx>(
o: &PredicateObligation<'tcx>,
) -> bool {
let infcx = &selcx.infcx().fork();
if resolve_negative_obligation(infcx, param_env, region_context, o) {
return true;
}
// Try to prove a negative obligation exist for super predicates
for o in util::elaborate_predicates(infcx.tcx, iter::once(o.predicate)) {
if resolve_negative_obligation(infcx, param_env, region_context, &o) {
return true;
}
}
false
}
#[instrument(level = "debug", skip(infcx))]
fn resolve_negative_obligation<'cx, 'tcx>(
infcx: &InferCtxt<'cx, 'tcx>,
param_env: ty::ParamEnv<'tcx>,
region_context: DefId,
o: &PredicateObligation<'tcx>,
) -> bool {
let tcx = infcx.tcx;
o.flip_polarity(tcx)
.map(|o| {
let mut fulfillment_cx = FulfillmentContext::new();
fulfillment_cx.register_predicate_obligation(infcx, o);
let errors = fulfillment_cx.select_all_or_error(infcx);
if !errors.is_empty() {
return false;
}
let Some(o) = o.flip_polarity(tcx) else {
return false;
};
let mut outlives_env = OutlivesEnvironment::new(param_env);
// FIXME -- add "assumed to be well formed" types into the `outlives_env`
let mut fulfillment_cx = FulfillmentContext::new();
fulfillment_cx.register_predicate_obligation(infcx, o);
// "Save" the accumulated implied bounds into the outlives environment
// (due to the FIXME above, there aren't any, but this step is still needed).
// The "body id" is given as `CRATE_HIR_ID`, which is the same body-id used
// by the "dummy" causes elsewhere (body-id is only relevant when checking
// function bodies with closures).
outlives_env.save_implied_bounds(CRATE_HIR_ID);
let errors = fulfillment_cx.select_all_or_error(infcx);
infcx.process_registered_region_obligations(
outlives_env.region_bound_pairs_map(),
Some(tcx.lifetimes.re_root_empty),
param_env,
);
if !errors.is_empty() {
return false;
}
let errors =
infcx.resolve_regions(region_context, &outlives_env, RegionckMode::default());
if !errors.is_empty() {
return false;
}
let mut outlives_env = OutlivesEnvironment::new(param_env);
// FIXME -- add "assumed to be well formed" types into the `outlives_env`
true
})
.unwrap_or(false)
// "Save" the accumulated implied bounds into the outlives environment
// (due to the FIXME above, there aren't any, but this step is still needed).
// The "body id" is given as `CRATE_HIR_ID`, which is the same body-id used
// by the "dummy" causes elsewhere (body-id is only relevant when checking
// function bodies with closures).
outlives_env.save_implied_bounds(CRATE_HIR_ID);
infcx.process_registered_region_obligations(
outlives_env.region_bound_pairs_map(),
Some(tcx.lifetimes.re_root_empty),
param_env,
);
let errors = infcx.resolve_regions(region_context, &outlives_env, RegionckMode::default());
if !errors.is_empty() {
return false;
}
true
}
pub fn trait_ref_is_knowable<'tcx>(

View file

@ -72,7 +72,7 @@ ENV PATH="/node-v14.4.0-linux-x64/bin:${PATH}"
# https://github.com/puppeteer/puppeteer/issues/375
#
# We also specify the version in case we need to update it to go around cache limitations.
RUN npm install -g browser-ui-test@0.8.1 --unsafe-perm=true
RUN npm install -g browser-ui-test@0.8.3 --unsafe-perm=true
ENV RUST_CONFIGURE_ARGS \
--build=x86_64-unknown-linux-gnu \

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@ -25,6 +25,7 @@ if [[ -n "${CI_ONLY_WHEN_SUBMODULES_CHANGED-}" ]]; then
elif ! (git diff --quiet "$BASE_COMMIT" -- \
src/test/rustdoc-gui \
src/librustdoc \
src/ci/docker/host-x86_64/x86_64-gnu-tools/Dockerfile \
src/tools/rustdoc-gui); then
# There was a change in either rustdoc or in its GUI tests.
echo "Rustdoc was updated"

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@ -0,0 +1,12 @@
// check-pass
#![feature(negative_impls)]
#![feature(with_negative_coherence)]
trait A {}
trait B: A {}
impl !A for u32 {}
impl !B for u32 {}
fn main() {}

View file

@ -1,3 +1,5 @@
// check-pass
#![feature(negative_impls)]
#![feature(rustc_attrs)]
#![feature(trait_alias)]
@ -13,7 +15,5 @@ impl !A for u32 {}
trait C {}
impl<T: AB> C for T {}
impl C for u32 {}
//~^ ERROR: conflicting implementations of trait `C` for type `u32` [E0119]
// FIXME this should work, we should implement an `assemble_neg_candidates` fn
fn main() {}

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@ -1,11 +0,0 @@
error[E0119]: conflicting implementations of trait `C` for type `u32`
--> $DIR/coherence-overlap-negate-alias-strict.rs:15:1
|
LL | impl<T: AB> C for T {}
| ------------------- first implementation here
LL | impl C for u32 {}
| ^^^^^^^^^^^^^^ conflicting implementation for `u32`
error: aborting due to previous error
For more information about this error, try `rustc --explain E0119`.

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@ -0,0 +1,18 @@
// check-pass
#![feature(negative_impls)]
#![feature(rustc_attrs)]
#![feature(with_negative_coherence)]
trait Trait1: Trait2 {}
trait Trait2 {}
struct MyType {}
impl !Trait2 for MyType {}
#[rustc_strict_coherence]
trait Foo {}
impl<T: Trait1> Foo for T {}
impl Foo for MyType {}
fn main() {}

@ -1 +1 @@
Subproject commit 7bc0c986217629e6c831edcb133532023a5aec63
Subproject commit 8e818ffa1b85f4e740c4096fd38c62b2b73f4d83