diff options
| -rw-r--r-- | compiler/rustc_hir_analysis/src/check/compare_method.rs | 18 |
1 files changed, 9 insertions, 9 deletions
diff --git a/compiler/rustc_hir_analysis/src/check/compare_method.rs b/compiler/rustc_hir_analysis/src/check/compare_method.rs index 6ee53436385..60eaad9b498 100644 --- a/compiler/rustc_hir_analysis/src/check/compare_method.rs +++ b/compiler/rustc_hir_analysis/src/check/compare_method.rs @@ -578,18 +578,18 @@ pub fn collect_trait_impl_trait_tys<'tcx>( // region substs that are synthesized during AST lowering. These are substs // that are appended to the parent substs (trait and trait method). However, // we're trying to infer the unsubstituted type value of the RPITIT inside - // the *impl*, so we can later use the impl's method substitutions to normalize - // an RPITIT to a concrete type. + // the *impl*, so we can later use the impl's method substs to normalize + // an RPITIT to a concrete type (`confirm_impl_trait_in_trait_candidate`). // // Due to the design of RPITITs, during AST lowering, we have no idea that - // an impl method is satisfying a trait method with RPITITs in it. Therefore, - // we don't have a list ofearly-bound region substs for the RPITIT in the impl. + // an impl method corresponds to a trait method with RPITITs in it. Therefore, + // we don't have a list of early-bound region substs for the RPITIT in the impl. // Since early region parameters are index-based, we can't just rebase these - // (trait method) early-bound region substs onto the impl, since region - // parameters are index-based, and there's no guarantee that the indices from - // the trait substs and impl substs line up -- so we subtract the number of - // trait substs and add the number of impl substs to *renumber* these early- - // bound regions to their corresponding indices in the impl's substitutions list. + // (trait method) early-bound region substs onto the impl, and there's no + // guarantee that the indices from the trait substs and impl substs line up. + // So to fix this, we subtract the number of trait substs and add the number of + // impl substs to *renumber* these early-bound regions to their corresponding + // indices in the impl's substitutions list. // // Also, we only need to account for a difference in trait and impl substs, // since we previously enforce that the trait method and impl method have the |