mGCA: Validate const literal against expected type #152001
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very cool :) thanks for working on this |
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…=oli-obk Dont strip const blocks in array lengths r? oli-obk mGCA now handles const blocks by *always* handling them during `lower_expr_to_const_arg_direct` instead of *sometimes* stripping them out at parse time. This is just generally a lot clearer/nicer but also means parsing isn't lossy which is just straight up wrong. We now use `MgcaDisambiguation::Direct` for const blocks because we "directly" represent a const block as `hir::ConstArgKind::Anon` :> The only time that an anon const for const generics uses `MgcaDisambiguation::AnonConst` is for unbraced literals. Once we properly support literals in `hir::ConstArgKind` (see rust-lang#152139 rust-lang#152001) then `MgcaDisambiguation` can be renamed to `AnonConstKind` with `TypeSystem` and `NonTypeSystem` variants. We can also get rid of `mgca_direct_lit_hack`. I expect this to be a very nice cleanup :) Fixes rust-lang/rustfmt#6788 The diff relating to passing spans around is to avoid a bunch of mGCA diagnostics changing from `const {}` to `{}`. I'm not entirely sure why this was happening. cc @rust-lang/rustfmt How do I run the tests in the rustfmt repo from here? `x test rustfmt` only seems to run like 100 tests and doesn't result in a `target/issue-6788.rs` getting created. I've verified locally that this formats correctly though
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…=oli-obk Dont strip const blocks in array lengths r? oli-obk mGCA now handles const blocks by *always* handling them during `lower_expr_to_const_arg_direct` instead of *sometimes* stripping them out at parse time. This is just generally a lot clearer/nicer but also means parsing isn't lossy which is just straight up wrong. We now use `MgcaDisambiguation::Direct` for const blocks because we "directly" represent a const block as `hir::ConstArgKind::Anon` :> The only time that an anon const for const generics uses `MgcaDisambiguation::AnonConst` is for unbraced literals. Once we properly support literals in `hir::ConstArgKind` (see rust-lang#152139 rust-lang#152001) then `MgcaDisambiguation` can be renamed to `AnonConstKind` with `TypeSystem` and `NonTypeSystem` variants. We can also get rid of `mgca_direct_lit_hack`. I expect this to be a very nice cleanup :) Fixes rust-lang/rustfmt#6788 The diff relating to passing spans around is to avoid a bunch of mGCA diagnostics changing from `const {}` to `{}`. I'm not entirely sure why this was happening. cc @rust-lang/rustfmt How do I run the tests in the rustfmt repo from here? `x test rustfmt` only seems to run like 100 tests and doesn't result in a `target/issue-6788.rs` getting created. I've verified locally that this formats correctly though
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…=oli-obk Dont strip const blocks in array lengths r? oli-obk mGCA now handles const blocks by *always* handling them during `lower_expr_to_const_arg_direct` instead of *sometimes* stripping them out at parse time. This is just generally a lot clearer/nicer but also means parsing isn't lossy which is just straight up wrong. We now use `MgcaDisambiguation::Direct` for const blocks because we "directly" represent a const block as `hir::ConstArgKind::Anon` :> The only time that an anon const for const generics uses `MgcaDisambiguation::AnonConst` is for unbraced literals. Once we properly support literals in `hir::ConstArgKind` (see rust-lang#152139 rust-lang#152001) then `MgcaDisambiguation` can be renamed to `AnonConstKind` with `TypeSystem` and `NonTypeSystem` variants. We can also get rid of `mgca_direct_lit_hack`. I expect this to be a very nice cleanup :) Fixes rust-lang/rustfmt#6788 The diff relating to passing spans around is to avoid a bunch of mGCA diagnostics changing from `const {}` to `{}`. I'm not entirely sure why this was happening. cc @rust-lang/rustfmt How do I run the tests in the rustfmt repo from here? `x test rustfmt` only seems to run like 100 tests and doesn't result in a `target/issue-6788.rs` getting created. I've verified locally that this formats correctly though
JonathanBrouwer
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…=oli-obk Dont strip const blocks in array lengths r? oli-obk mGCA now handles const blocks by *always* handling them during `lower_expr_to_const_arg_direct` instead of *sometimes* stripping them out at parse time. This is just generally a lot clearer/nicer but also means parsing isn't lossy which is just straight up wrong. We now use `MgcaDisambiguation::Direct` for const blocks because we "directly" represent a const block as `hir::ConstArgKind::Anon` :> The only time that an anon const for const generics uses `MgcaDisambiguation::AnonConst` is for unbraced literals. Once we properly support literals in `hir::ConstArgKind` (see rust-lang#152139 rust-lang#152001) then `MgcaDisambiguation` can be renamed to `AnonConstKind` with `TypeSystem` and `NonTypeSystem` variants. We can also get rid of `mgca_direct_lit_hack`. I expect this to be a very nice cleanup :) Fixes rust-lang/rustfmt#6788 The diff relating to passing spans around is to avoid a bunch of mGCA diagnostics changing from `const {}` to `{}`. I'm not entirely sure why this was happening. cc @rust-lang/rustfmt How do I run the tests in the rustfmt repo from here? `x test rustfmt` only seems to run like 100 tests and doesn't result in a `target/issue-6788.rs` getting created. I've verified locally that this formats correctly though
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Rollup merge of #152234 - BoxyUwU:dont_strip_const_blocks, r=oli-obk Dont strip const blocks in array lengths r? oli-obk mGCA now handles const blocks by *always* handling them during `lower_expr_to_const_arg_direct` instead of *sometimes* stripping them out at parse time. This is just generally a lot clearer/nicer but also means parsing isn't lossy which is just straight up wrong. We now use `MgcaDisambiguation::Direct` for const blocks because we "directly" represent a const block as `hir::ConstArgKind::Anon` :> The only time that an anon const for const generics uses `MgcaDisambiguation::AnonConst` is for unbraced literals. Once we properly support literals in `hir::ConstArgKind` (see #152139 #152001) then `MgcaDisambiguation` can be renamed to `AnonConstKind` with `TypeSystem` and `NonTypeSystem` variants. We can also get rid of `mgca_direct_lit_hack`. I expect this to be a very nice cleanup :) Fixes rust-lang/rustfmt#6788 The diff relating to passing spans around is to avoid a bunch of mGCA diagnostics changing from `const {}` to `{}`. I'm not entirely sure why this was happening. cc @rust-lang/rustfmt How do I run the tests in the rustfmt repo from here? `x test rustfmt` only seems to run like 100 tests and doesn't result in a `target/issue-6788.rs` getting created. I've verified locally that this formats correctly though
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Haha, ICE occurs in other tests... |
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In ten crash tests, the ICE disappeared; however, in tests/crashes/117460.rs, tests/crashes/114212-2.rs and tests/crashes/114212.rs, adding the main function caused the ICE to occur again.
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| //! Regression test for <https://github.com/rust-lang/rust/issues/116554> | |||
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This issue was closed; is there a need to add further testing?
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unsure, I will look over all the GCE tests (outside of this PR) at some point soon and see which ones are worth keeping
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| //@ known-bug: #101036 | |||
| #![feature(generic_const_exprs)] | |||
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cool! sorry for a lot of comments but this is looking really good :) |
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In my current code, an ICE will occur in the Looking at the stacktrace and log, it appears that after returning How would you recommend handling this situation? |
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No worries at all — I really appreciate the detailed feedback. Thanks for taking the time to review (_ _) |
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does it still ICE after removing some of the checks you had for types being equal? If so I'd just remove that test |
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Co-authored-by: Boxy <rust@boxyuwu.dev>
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The job Click to see the possible cause of the failure (guessed by this bot) |
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| .map(|l| tcx.at(expr.span).lit_to_const(l)) | ||
| lit_input.and_then(|l| { | ||
| tcx.at(expr.span) | ||
| .lit_to_const(l) |
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so we now get a bunch of extra errors I think because this succeeds in more cases and results in duplication between the type checking errors of the anon const this was derived from, and type checking errors for the const arg matching the thing its a parameter to.
I think it would probably make sense (for diagnostics reasons) to do like .filter(|| const_lit_matches_ty()) so that we only do this fast path if the types are ok 🤔
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close: #151625
close: #150983
todo
lit_to_constmethod test coverage