diff options
Diffstat (limited to 'compiler/rustc_middle/src/traits/specialization_graph.rs')
| -rw-r--r-- | compiler/rustc_middle/src/traits/specialization_graph.rs | 19 |
1 files changed, 16 insertions, 3 deletions
diff --git a/compiler/rustc_middle/src/traits/specialization_graph.rs b/compiler/rustc_middle/src/traits/specialization_graph.rs index 0a2819fee..cccedc9ec 100644 --- a/compiler/rustc_middle/src/traits/specialization_graph.rs +++ b/compiler/rustc_middle/src/traits/specialization_graph.rs @@ -1,3 +1,4 @@ +use crate::error::StrictCoherenceNeedsNegativeCoherence; use crate::ty::fast_reject::SimplifiedType; use crate::ty::visit::TypeVisitable; use crate::ty::{self, TyCtxt}; @@ -65,9 +66,21 @@ impl OverlapMode { if with_negative_coherence { if strict_coherence { OverlapMode::Strict } else { OverlapMode::WithNegative } - } else if strict_coherence { - bug!("To use strict_coherence you need to set with_negative_coherence feature flag"); } else { + if strict_coherence { + let attr_span = trait_id + .as_local() + .into_iter() + .flat_map(|local_def_id| { + tcx.hir().attrs(tcx.hir().local_def_id_to_hir_id(local_def_id)) + }) + .find(|attr| attr.has_name(sym::rustc_strict_coherence)) + .map(|attr| attr.span); + tcx.sess.emit_err(StrictCoherenceNeedsNegativeCoherence { + span: tcx.def_span(trait_id), + attr_span, + }); + } OverlapMode::Stable } } @@ -249,7 +262,7 @@ pub fn ancestors<'tcx>( if let Some(reported) = specialization_graph.has_errored { Err(reported) - } else if let Some(reported) = tcx.type_of(start_from_impl).error_reported() { + } else if let Err(reported) = tcx.type_of(start_from_impl).error_reported() { Err(reported) } else { Ok(Ancestors { |