Fix trait upcasting to dyn type with no principal when there are projections #139421
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…l-with-proj, r=oli-obk Fix trait upcasting to dyn type with no principal when there are projections rust-lang#126660 (which I had originally authored, lol) had a subtle bug that is the moral equivalent of rust-lang#114036, which is that when upcasting from `dyn Principal<Projection = Ty> + AutoTrait` to `dyn AutoTrait`, we were dropping the trait ref for `Principal` but not its projections (if there were any). With debug assertions enabled, this triggers the assertion I luckily added in a2a0cfe, but even without debug assertions this is a logical bug since we had a dyn type with just a projection bound but no principal, so it caused a type mismatch. This does not need an FCP because this should've been covered by the FCP in rust-lang#126660, but we just weren't testing a case when casting from a `dyn` type with projections 😸 Fixes rust-lang#139418 r? `@oli-obk` (or anyone)
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…iaskrgr Rollup of 7 pull requests Successful merges: - rust-lang#139124 (compiler: report error when trait object type param reference self) - rust-lang#139346 (Don't construct preds w escaping bound vars in `diagnostic_hir_wf_check`) - rust-lang#139379 (Use delayed bug for normalization errors in drop elaboration) - rust-lang#139421 (Fix trait upcasting to dyn type with no principal when there are projections) - rust-lang#139468 (Don't call `Span::with_parent` on the good path in `has_stashed_diagnostic`) - rust-lang#139476 (rm `RegionInferenceContext::var_infos`) - rust-lang#139490 (Update some comment/docs related to "extern intrinsic" removal) r? `@ghost` `@rustbot` modify labels: rollup
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…l-with-proj, r=oli-obk Fix trait upcasting to dyn type with no principal when there are projections rust-lang#126660 (which I had originally authored, lol) had a subtle bug that is the moral equivalent of rust-lang#114036, which is that when upcasting from `dyn Principal<Projection = Ty> + AutoTrait` to `dyn AutoTrait`, we were dropping the trait ref for `Principal` but not its projections (if there were any). With debug assertions enabled, this triggers the assertion I luckily added in a2a0cfe, but even without debug assertions this is a logical bug since we had a dyn type with just a projection bound but no principal, so it caused a type mismatch. This does not need an FCP because this should've been covered by the FCP in rust-lang#126660, but we just weren't testing a case when casting from a `dyn` type with projections 😸 Fixes rust-lang#139418 r? ``@oli-obk`` (or anyone)
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…iaskrgr Rollup of 6 pull requests Successful merges: - rust-lang#139124 (compiler: report error when trait object type param reference self) - rust-lang#139346 (Don't construct preds w escaping bound vars in `diagnostic_hir_wf_check`) - rust-lang#139421 (Fix trait upcasting to dyn type with no principal when there are projections) - rust-lang#139468 (Don't call `Span::with_parent` on the good path in `has_stashed_diagnostic`) - rust-lang#139476 (rm `RegionInferenceContext::var_infos`) - rust-lang#139490 (Update some comment/docs related to "extern intrinsic" removal) r? `@ghost` `@rustbot` modify labels: rollup
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…l-with-proj, r=oli-obk Fix trait upcasting to dyn type with no principal when there are projections rust-lang#126660 (which I had originally authored, lol) had a subtle bug that is the moral equivalent of rust-lang#114036, which is that when upcasting from `dyn Principal<Projection = Ty> + AutoTrait` to `dyn AutoTrait`, we were dropping the trait ref for `Principal` but not its projections (if there were any). With debug assertions enabled, this triggers the assertion I luckily added in a2a0cfe, but even without debug assertions this is a logical bug since we had a dyn type with just a projection bound but no principal, so it caused a type mismatch. This does not need an FCP because this should've been covered by the FCP in rust-lang#126660, but we just weren't testing a case when casting from a `dyn` type with projections 😸 Fixes rust-lang#139418 r? ```@oli-obk``` (or anyone)
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…errors Rollup of 19 pull requests Successful merges: - rust-lang#138676 (Implement overflow for infinite implied lifetime bounds) - rust-lang#139024 (Make error message for missing fields with `..` and without `..` more consistent) - rust-lang#139098 (Tell LLVM about impossible niche tags) - rust-lang#139124 (compiler: report error when trait object type param reference self) - rust-lang#139321 (Update to new rinja version (askama)) - rust-lang#139346 (Don't construct preds w escaping bound vars in `diagnostic_hir_wf_check`) - rust-lang#139386 (make it possible to use stage0 libtest on compiletest) - rust-lang#139421 (Fix trait upcasting to dyn type with no principal when there are projections) - rust-lang#139468 (Don't call `Span::with_parent` on the good path in `has_stashed_diagnostic`) - rust-lang#139476 (rm `RegionInferenceContext::var_infos`) - rust-lang#139481 (Add job summary links to post-merge report) - rust-lang#139485 (compiletest: Stricter parsing for diagnostic kinds) - rust-lang#139490 (Update some comment/docs related to "extern intrinsic" removal) - rust-lang#139491 (Update books) - rust-lang#139496 (Revert r-a changes of rust-lang#139455) - rust-lang#139500 (document panic behavior of Vec::resize and Vec::resize_with) - rust-lang#139501 (Fix stack overflow in exhaustiveness due to recursive HIR opaque hidden types) - rust-lang#139504 (add missing word in doc comment) - rust-lang#139507 (compiletest: Trim whitespace from environment variable names) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup of 10 pull requests Successful merges: - rust-lang#138676 (Implement overflow for infinite implied lifetime bounds) - rust-lang#139024 (Make error message for missing fields with `..` and without `..` more consistent) - rust-lang#139098 (Tell LLVM about impossible niche tags) - rust-lang#139124 (compiler: report error when trait object type param reference self) - rust-lang#139321 (Update to new rinja version (askama)) - rust-lang#139346 (Don't construct preds w escaping bound vars in `diagnostic_hir_wf_check`) - rust-lang#139386 (make it possible to use stage0 libtest on compiletest) - rust-lang#139421 (Fix trait upcasting to dyn type with no principal when there are projections) - rust-lang#139464 (Allow for reparsing failure when reparsing a pasted metavar.) - rust-lang#139490 (Update some comment/docs related to "extern intrinsic" removal) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of rust-lang#139421 - compiler-errors:upcast-no-principal-with-proj, r=oli-obk Fix trait upcasting to dyn type with no principal when there are projections rust-lang#126660 (which I had originally authored, lol) had a subtle bug that is the moral equivalent of rust-lang#114036, which is that when upcasting from `dyn Principal<Projection = Ty> + AutoTrait` to `dyn AutoTrait`, we were dropping the trait ref for `Principal` but not its projections (if there were any). With debug assertions enabled, this triggers the assertion I luckily added in a2a0cfe, but even without debug assertions this is a logical bug since we had a dyn type with just a projection bound but no principal, so it caused a type mismatch. This does not need an FCP because this should've been covered by the FCP in rust-lang#126660, but we just weren't testing a case when casting from a `dyn` type with projections 😸 Fixes rust-lang#139418 r? ````@oli-obk```` (or anyone)
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#126660 (which I had originally authored, lol) had a subtle bug that is the moral equivalent of #114036, which is that when upcasting from
dyn Principal<Projection = Ty> + AutoTraittodyn AutoTrait, we were dropping the trait ref forPrincipalbut not its projections (if there were any).With debug assertions enabled, this triggers the assertion I luckily added in a2a0cfe, but even without debug assertions this is a logical bug since we had a dyn type with just a projection bound but no principal, so it caused a type mismatch.
This does not need an FCP because this should've been covered by the FCP in #126660, but we just weren't testing a case when casting from a
dyntype with projections 😸Fixes #139418
r? @oli-obk (or anyone)