diff options
| -rw-r--r-- | compiler/rustc_index_macros/src/lib.rs | 3 | ||||
| -rw-r--r-- | compiler/rustc_trait_selection/src/traits/specialize/mod.rs | 32 |
2 files changed, 22 insertions, 13 deletions
diff --git a/compiler/rustc_index_macros/src/lib.rs b/compiler/rustc_index_macros/src/lib.rs index ac374a41eb6..b0bf4554ba8 100644 --- a/compiler/rustc_index_macros/src/lib.rs +++ b/compiler/rustc_index_macros/src/lib.rs @@ -36,6 +36,9 @@ mod newtype; feature = "nightly", allow_internal_unstable(step_trait, rustc_attrs, trusted_step, spec_option_partial_eq) )] +// FIXME: Remove the above comment about `min_specialization` once bootstrap is bumped, +// and the corresponding one on SpecOptionPartialEq +#[cfg_attr(all(feature = "nightly", not(bootstrap)), allow_internal_unstable(min_specialization))] pub fn newtype_index(input: TokenStream) -> TokenStream { newtype::newtype(input) } diff --git a/compiler/rustc_trait_selection/src/traits/specialize/mod.rs b/compiler/rustc_trait_selection/src/traits/specialize/mod.rs index d3862451a01..b37d9714ddd 100644 --- a/compiler/rustc_trait_selection/src/traits/specialize/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/specialize/mod.rs @@ -142,23 +142,29 @@ pub fn translate_args_with_cause<'tcx>( pub(super) fn specializes(tcx: TyCtxt<'_>, (impl1_def_id, impl2_def_id): (DefId, DefId)) -> bool { // The feature gate should prevent introducing new specializations, but not // taking advantage of upstream ones. + // If specialization is enabled for this crate then no extra checks are needed. + // If it's not, and either of the `impl`s is local to this crate, then this definitely + // isn't specializing - unless specialization is enabled for the `impl` span, + // e.g. if it comes from an `allow_internal_unstable` macro let features = tcx.features(); let specialization_enabled = features.specialization || features.min_specialization; - if !specialization_enabled && impl1_def_id.is_local() { - let span = tcx.def_span(impl1_def_id); - if !span.allows_unstable(sym::specialization) - && !span.allows_unstable(sym::min_specialization) - { - return false; + if !specialization_enabled { + if impl1_def_id.is_local() { + let span = tcx.def_span(impl1_def_id); + if !span.allows_unstable(sym::specialization) + && !span.allows_unstable(sym::min_specialization) + { + return false; + } } - } - if !specialization_enabled && impl2_def_id.is_local() { - let span = tcx.def_span(impl2_def_id); - if !span.allows_unstable(sym::specialization) - && !span.allows_unstable(sym::min_specialization) - { - return false; + if impl2_def_id.is_local() { + let span = tcx.def_span(impl2_def_id); + if !span.allows_unstable(sym::specialization) + && !span.allows_unstable(sym::min_specialization) + { + return false; + } } } |