Auto merge of #136311 - compiler-errors:vtable-fixes-2, r= · rust-lang/rust@cf8986d (original) (raw)
`@@ -318,9 +318,17 @@ pub(crate) fn first_method_vtable_slot<'tcx>(tcx: TyCtxt<'tcx>, key: ty::TraitRe
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`bug!();
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`};
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`let source_principal = tcx.instantiate_bound_regions_with_erased(
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``
`-
source.principal().unwrap().with_self_ty(tcx, tcx.types.trait_object_dummy_self),
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source.principal().unwrap().with_self_ty(tcx, key.self_ty()),
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`);
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``
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// We're monomorphizing a call to a dyn trait object that can never be constructed.
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if tcx.instantiate_and_check_impossible_predicates((
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source_principal.def_id,
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source_principal.args,
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)) {
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return 0;
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}
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`let target_principal = ty::ExistentialTraitRef::erase_self_ty(tcx, key);
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`let vtable_segment_callback = {
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`@@ -373,19 +381,27 @@ pub(crate) fn supertrait_vtable_slot<'tcx>(
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`let (source, target) = key;
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`` // If the target principal is None, we can just return None.
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``
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let ty::Dynamic(target, _, _) = *target.kind() else {
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let ty::Dynamic(target_data, _, _) = *target.kind() else {
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`bug!();
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`};
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``
`-
let target_principal = tcx.instantiate_bound_regions_with_erased(target.principal()?);
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let target_principal = tcx.instantiate_bound_regions_with_erased(target_data.principal()?);
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`// Given that we have a target principal, it is a bug for there not to be a source principal.
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let ty::Dynamic(source, _, _) = *source.kind() else {
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let ty::Dynamic(source_data, _, _) = *source.kind() else {
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`bug!();
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`};
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`let source_principal = tcx.instantiate_bound_regions_with_erased(
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`-
source.principal().unwrap().with_self_ty(tcx, tcx.types.trait_object_dummy_self),
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source_data.principal().unwrap().with_self_ty(tcx, source),
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`);
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``
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// We're monomorphizing a dyn trait object upcast that can never be constructed.
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if tcx.instantiate_and_check_impossible_predicates((
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source_principal.def_id,
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source_principal.args,
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)) {
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return None;
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}
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`let vtable_segment_callback = {
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`let mut vptr_offset = 0;
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`move |segment| {
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