diff options
Diffstat (limited to 'compiler/rustc_infer/src')
| -rw-r--r-- | compiler/rustc_infer/src/infer/canonical/query_response.rs | 11 |
1 files changed, 4 insertions, 7 deletions
diff --git a/compiler/rustc_infer/src/infer/canonical/query_response.rs b/compiler/rustc_infer/src/infer/canonical/query_response.rs index a20cd31113a..b3959113d5d 100644 --- a/compiler/rustc_infer/src/infer/canonical/query_response.rs +++ b/compiler/rustc_infer/src/infer/canonical/query_response.rs @@ -87,14 +87,11 @@ impl<'tcx> InferCtxt<'tcx> { { // While we ignore region constraints and pending obligations, // we do return constrained opaque types to avoid unconstrained - // inference variables in the response. This is still slightly - // insufficient as ambiguous `Projection` obligations have the - // same issue. + // inference variables in the response. This is important as we want + // to check that opaques in deref steps stay unconstrained. // - // FIXME(-Znext-solver): We could alternatively extend the `var_values` - // each time we call `make_query_response_ignoring_pending_obligations` - // and equate inference variables created inside of the query this way. - // This is what we do for `CanonicalState` and is probably a bit nicer. + // This doesn't handle the more general case for non-opaques as + // ambiguous `Projection` obligations have same the issue. let opaque_types = if self.next_trait_solver() { self.inner .borrow_mut() |