…thercote

Make the ordering of non-terminal binds in ambiguity error messages deterministic

My next PR will rework macro parsing to use a DFS approach instead of a BFS. It will change the order in which the parsing space is explored, and while this does not change the behavior of parsing in success cases, it did cause changes to some error messages; in particular, when an ambiguity error occurs, it would sometimes report non-terminal binds in a different order (e.g. in ```error: local ambiguity when calling macro `foo`: multiple parsing options: built-in NTs ident ('i') or ident ('j').```). I realized that the current macro parsing code does not enforce a particular order for those binds, so this PR 1) adds a test case for strange bind orderings and 2) makes the bind ordering deterministic (in line with the ordering of those binds in the macro definition, which was how binds tended to be ordered anyway).

Ideally reviewed commit-by-commit.

r? @nnethercote

…thercote

Make the ordering of non-terminal binds in ambiguity error messages deterministic

My next PR will rework macro parsing to use a DFS approach instead of a BFS. It will change the order in which the parsing space is explored, and while this does not change the behavior of parsing in success cases, it did cause changes to some error messages; in particular, when an ambiguity error occurs, it would sometimes report non-terminal binds in a different order (e.g. in ```error: local ambiguity when calling macro `foo`: multiple parsing options: built-in NTs ident ('i') or ident ('j').```). I realized that the current macro parsing code does not enforce a particular order for those binds, so this PR 1) adds a test case for strange bind orderings and 2) makes the bind ordering deterministic (in line with the ordering of those binds in the macro definition, which was how binds tended to be ordered anyway).

Ideally reviewed commit-by-commit.

r? @nnethercote

…uwer

Rollup of 18 pull requests

Successful merges:

 - #158871 (add relnotes for 1.97.0)
 - #150946 (intrinsics: Add a fallback for non-const libm float functions)
 - #158617 (allow mGCA const arguments to fall back to anon consts)
 - #158645 (Fix splat ICEs and ban it in closures)
 - #158655 (Fix coroutine MIR saved local remapping)
 - #158666 (Carry the `b_offset` inside `BackendRepr::ScalarPair`)
 - #158920 (Update wasm-component-ld to 0.5.26)
 - #158926 (wrapping_sh* methods: clarify underspecified reference)
 - #158927 (add core test run with `-Zforce-intrinsic-fallback`)
 - #151379 (Stabilize `VecDeque::retain_back` from `truncate_front`)
 - #158807 (Add regression test for CString::clone_into unwind safety)
 - #158862 (Fix the span for parameter suggestion )
 - #158883 (tests: fix enum-match.rs to handle LLVM 23)
 - #158894 (Make the ordering of non-terminal binds in ambiguity error messages deterministic)
 - #158902 (add codegen test for range length bound propagation)
 - #158913 (Update `browser-ui-test` version to `0.24.1`)
 - #158935 (std: support real fd methods on Emscripten)
 - #158951 (Merge three `MaxUniverse`s into one)

…uwer

Rollup of 18 pull requests

Successful merges:

 - #158871 (add relnotes for 1.97.0)
 - #150946 (intrinsics: Add a fallback for non-const libm float functions)
 - #158617 (allow mGCA const arguments to fall back to anon consts)
 - #158645 (Fix splat ICEs and ban it in closures)
 - #158655 (Fix coroutine MIR saved local remapping)
 - #158666 (Carry the `b_offset` inside `BackendRepr::ScalarPair`)
 - #158920 (Update wasm-component-ld to 0.5.26)
 - #158926 (wrapping_sh* methods: clarify underspecified reference)
 - #158927 (add core test run with `-Zforce-intrinsic-fallback`)
 - #151379 (Stabilize `VecDeque::retain_back` from `truncate_front`)
 - #158807 (Add regression test for CString::clone_into unwind safety)
 - #158862 (Fix the span for parameter suggestion )
 - #158883 (tests: fix enum-match.rs to handle LLVM 23)
 - #158894 (Make the ordering of non-terminal binds in ambiguity error messages deterministic)
 - #158902 (add codegen test for range length bound propagation)
 - #158913 (Update `browser-ui-test` version to `0.24.1`)
 - #158935 (std: support real fd methods on Emscripten)
 - #158951 (Merge three `MaxUniverse`s into one)

…uwer

Rollup of 18 pull requests

Successful merges:

 - #158871 (add relnotes for 1.97.0)
 - #150946 (intrinsics: Add a fallback for non-const libm float functions)
 - #158617 (allow mGCA const arguments to fall back to anon consts)
 - #158645 (Fix splat ICEs and ban it in closures)
 - #158655 (Fix coroutine MIR saved local remapping)
 - #158666 (Carry the `b_offset` inside `BackendRepr::ScalarPair`)
 - #158920 (Update wasm-component-ld to 0.5.26)
 - #158926 (wrapping_sh* methods: clarify underspecified reference)
 - #158927 (add core test run with `-Zforce-intrinsic-fallback`)
 - #151379 (Stabilize `VecDeque::retain_back` from `truncate_front`)
 - #158807 (Add regression test for CString::clone_into unwind safety)
 - #158862 (Fix the span for parameter suggestion )
 - #158883 (tests: fix enum-match.rs to handle LLVM 23)
 - #158894 (Make the ordering of non-terminal binds in ambiguity error messages deterministic)
 - #158902 (add codegen test for range length bound propagation)
 - #158913 (Update `browser-ui-test` version to `0.24.1`)
 - #158935 (std: support real fd methods on Emscripten)
 - #158951 (Merge three `MaxUniverse`s into one)

…thercote

Make the ordering of non-terminal binds in ambiguity error messages deterministic

My next PR will rework macro parsing to use a DFS approach instead of a BFS. It will change the order in which the parsing space is explored, and while this does not change the behavior of parsing in success cases, it did cause changes to some error messages; in particular, when an ambiguity error occurs, it would sometimes report non-terminal binds in a different order (e.g. in ```error: local ambiguity when calling macro `foo`: multiple parsing options: built-in NTs ident ('i') or ident ('j').```). I realized that the current macro parsing code does not enforce a particular order for those binds, so this PR 1) adds a test case for strange bind orderings and 2) makes the bind ordering deterministic (in line with the ordering of those binds in the macro definition, which was how binds tended to be ordered anyway).

Ideally reviewed commit-by-commit.

r? @nnethercote

Rollup of 23 pull requests

Successful merges:

 - #158968 (stdarch subtree update)
 - #154445 (rustdoc: Represent `--output-format=json` coverage and ir differently)
 - #158495 (Rename HAS_CT_PROJECTION to HAS_CONST_ALIAS)
 - #158666 (Carry the `b_offset` inside `BackendRepr::ScalarPair`)
 - #158870 (std: merge the unix-like io::error modules into one file)
 - #158920 (Update wasm-component-ld to 0.5.26)
 - #158926 (wrapping_sh* methods: clarify underspecified reference)
 - #158927 (add core test run with `-Zforce-intrinsic-fallback`)
 - #158932 (Do not build the compiler when invoking `x perf compare`)
 - #158937 (Emit the emscripten entry point as `__main_argc_argv`)
 - #151379 (Stabilize `VecDeque::retain_back` from `truncate_front`)
 - #156144 (Better docs for PartialEq (includes macro rename))
 - #156548 ( Library support for aarch64-unknown-linux-pauthtest target)
 - #157995 (`Vec::dedup_by` docs explicit function argument order)
 - #158307 (CI job for parallel frontend ui tests)
 - #158741 (Simplify `Option::into_flat_iter` signature)
 - #158807 (Add regression test for CString::clone_into unwind safety)
 - #158862 (Fix the span for parameter suggestion )
 - #158894 (Make the ordering of non-terminal binds in ambiguity error messages deterministic)
 - #158902 (add codegen test for range length bound propagation)
 - #158913 (Update `browser-ui-test` version to `0.24.1`)
 - #158935 (std: support real fd methods on Emscripten)
 - #158978 (Add regression test for too-big by-value ABI args)

Rollup merge of #158894 - bal-e:ambiguity-nt-ordering, r=nnethercote

Make the ordering of non-terminal binds in ambiguity error messages deterministic

My next PR will rework macro parsing to use a DFS approach instead of a BFS. It will change the order in which the parsing space is explored, and while this does not change the behavior of parsing in success cases, it did cause changes to some error messages; in particular, when an ambiguity error occurs, it would sometimes report non-terminal binds in a different order (e.g. in ```error: local ambiguity when calling macro `foo`: multiple parsing options: built-in NTs ident ('i') or ident ('j').```). I realized that the current macro parsing code does not enforce a particular order for those binds, so this PR 1) adds a test case for strange bind orderings and 2) makes the bind ordering deterministic (in line with the ordering of those binds in the macro definition, which was how binds tended to be ordered anyway).

Ideally reviewed commit-by-commit.

r? @nnethercote

Rollup of 23 pull requests

Successful merges:

 - rust-lang/rust#158968 (stdarch subtree update)
 - rust-lang/rust#154445 (rustdoc: Represent `--output-format=json` coverage and ir differently)
 - rust-lang/rust#158495 (Rename HAS_CT_PROJECTION to HAS_CONST_ALIAS)
 - rust-lang/rust#158666 (Carry the `b_offset` inside `BackendRepr::ScalarPair`)
 - rust-lang/rust#158870 (std: merge the unix-like io::error modules into one file)
 - rust-lang/rust#158920 (Update wasm-component-ld to 0.5.26)
 - rust-lang/rust#158926 (wrapping_sh* methods: clarify underspecified reference)
 - rust-lang/rust#158927 (add core test run with `-Zforce-intrinsic-fallback`)
 - rust-lang/rust#158932 (Do not build the compiler when invoking `x perf compare`)
 - rust-lang/rust#158937 (Emit the emscripten entry point as `__main_argc_argv`)
 - rust-lang/rust#151379 (Stabilize `VecDeque::retain_back` from `truncate_front`)
 - rust-lang/rust#156144 (Better docs for PartialEq (includes macro rename))
 - rust-lang/rust#156548 ( Library support for aarch64-unknown-linux-pauthtest target)
 - rust-lang/rust#157995 (`Vec::dedup_by` docs explicit function argument order)
 - rust-lang/rust#158307 (CI job for parallel frontend ui tests)
 - rust-lang/rust#158741 (Simplify `Option::into_flat_iter` signature)
 - rust-lang/rust#158807 (Add regression test for CString::clone_into unwind safety)
 - rust-lang/rust#158862 (Fix the span for parameter suggestion )
 - rust-lang/rust#158894 (Make the ordering of non-terminal binds in ambiguity error messages deterministic)
 - rust-lang/rust#158902 (add codegen test for range length bound propagation)
 - rust-lang/rust#158913 (Update `browser-ui-test` version to `0.24.1`)
 - rust-lang/rust#158935 (std: support real fd methods on Emscripten)
 - rust-lang/rust#158978 (Add regression test for too-big by-value ABI args)

Preparatory changes for macro parsing BFS->DFS

This PR contains some miscellaneous commits I accumulated while working on the BFS->DFS change. Their goal is to simplify the code and clarifying existing behavior. It is a conceptual follow-up to #158577. High-level overview:

- Adds context about the current match arm to `Tracker` through the new `Tracker::prepare()`, so that the `WhichMatcher` parameter is available implicitly. In a later PR, this will be used to reference `MatcherLoc`s by index.

- Reformulates matching failures to work more like ambiguity errors wrt. `Tracker`; `Tracker::build_failure()` (which would build a failure consumed by `Tracker::after_arm()`) becomes `Tracker::failure()` which eagerly processes the error. This removes the need for `ParseResult::Failure` to store any data at all. This relies on the match arm context provided by `Tracker::prepare()`.

- There is a subtle edge case involving `token::Eof` and non-terminal parsing; `Parser::nonterminal_may_begin_with()` would sometimes return `true` for `token::Eof`, even though the non-terminal parse would never be attempted. `TtParser` did not check `bb_mps` when handling `token::Eof`, so non-terminal parses at EOF were being silently dropped. I changed `Parser::nonterminal_may_begin_with()` to always return `false` for `token::Eof`, making this behavior much more visible. I added a test case to make sure meta-variables return the same error uniformly when parsed against EOF.

Contains #158894, which should be merged soon (after which I'll rebase onto `main`).

Best reviewed commit-by-commit.

r? @nnethercote

Preparatory changes for macro parsing BFS->DFS

This PR contains some miscellaneous commits I accumulated while working on the BFS->DFS change. Their goal is to simplify the code and clarifying existing behavior. It is a conceptual follow-up to #158577. High-level overview:

- Adds context about the current match arm to `Tracker` through the new `Tracker::prepare()`, so that the `WhichMatcher` parameter is available implicitly. In a later PR, this will be used to reference `MatcherLoc`s by index.

- Reformulates matching failures to work more like ambiguity errors wrt. `Tracker`; `Tracker::build_failure()` (which would build a failure consumed by `Tracker::after_arm()`) becomes `Tracker::failure()` which eagerly processes the error. This removes the need for `ParseResult::Failure` to store any data at all. This relies on the match arm context provided by `Tracker::prepare()`.

- There is a subtle edge case involving `token::Eof` and non-terminal parsing; `Parser::nonterminal_may_begin_with()` would sometimes return `true` for `token::Eof`, even though the non-terminal parse would never be attempted. `TtParser` did not check `bb_mps` when handling `token::Eof`, so non-terminal parses at EOF were being silently dropped. I changed `Parser::nonterminal_may_begin_with()` to always return `false` for `token::Eof`, making this behavior much more visible. I added a test case to make sure meta-variables return the same error uniformly when parsed against EOF.

Contains #158894, which should be merged soon (after which I'll rebase onto `main`).

Best reviewed commit-by-commit.

r? @nnethercote

Preparatory changes for macro parsing BFS->DFS



This PR contains some miscellaneous commits I accumulated while working on the BFS->DFS change. Their goal is to simplify the code and clarifying existing behavior. It is a conceptual follow-up to #158577. High-level overview:

- Adds context about the current match arm to `Tracker` through the new `Tracker::prepare()`, so that the `WhichMatcher` parameter is available implicitly. In a later PR, this will be used to reference `MatcherLoc`s by index.

- Reformulates matching failures to work more like ambiguity errors wrt. `Tracker`; `Tracker::build_failure()` (which would build a failure consumed by `Tracker::after_arm()`) becomes `Tracker::failure()` which eagerly processes the error. This removes the need for `ParseResult::Failure` to store any data at all. This relies on the match arm context provided by `Tracker::prepare()`.

- There is a subtle edge case involving `token::Eof` and non-terminal parsing; `Parser::nonterminal_may_begin_with()` would sometimes return `true` for `token::Eof`, even though the non-terminal parse would never be attempted. `TtParser` did not check `bb_mps` when handling `token::Eof`, so non-terminal parses at EOF were being silently dropped. I changed `Parser::nonterminal_may_begin_with()` to always return `false` for `token::Eof`, making this behavior much more visible. I added a test case to make sure meta-variables return the same error uniformly when parsed against EOF.

Contains #158894, which should be merged soon (after which I'll rebase onto `main`).

Best reviewed commit-by-commit.

r? @nnethercote

Preparatory changes for macro parsing BFS->DFS



This PR contains some miscellaneous commits I accumulated while working on the BFS->DFS change. Their goal is to simplify the code and clarifying existing behavior. It is a conceptual follow-up to rust-lang/rust#158577. High-level overview:

- Adds context about the current match arm to `Tracker` through the new `Tracker::prepare()`, so that the `WhichMatcher` parameter is available implicitly. In a later PR, this will be used to reference `MatcherLoc`s by index.

- Reformulates matching failures to work more like ambiguity errors wrt. `Tracker`; `Tracker::build_failure()` (which would build a failure consumed by `Tracker::after_arm()`) becomes `Tracker::failure()` which eagerly processes the error. This removes the need for `ParseResult::Failure` to store any data at all. This relies on the match arm context provided by `Tracker::prepare()`.

- There is a subtle edge case involving `token::Eof` and non-terminal parsing; `Parser::nonterminal_may_begin_with()` would sometimes return `true` for `token::Eof`, even though the non-terminal parse would never be attempted. `TtParser` did not check `bb_mps` when handling `token::Eof`, so non-terminal parses at EOF were being silently dropped. I changed `Parser::nonterminal_may_begin_with()` to always return `false` for `token::Eof`, making this behavior much more visible. I added a test case to make sure meta-variables return the same error uniformly when parsed against EOF.

Contains rust-lang/rust#158894, which should be merged soon (after which I'll rebase onto `main`).

Best reviewed commit-by-commit.

r? @nnethercote

Eagerly check for ambiguity in macro parsing

This PR implements an important step leading up to the BFS->DFS change: it makes ambiguity detection (as occurs when parsing meta-variables and reaching EOF) eager. Rather than accumulating the `bb_mps` and `eof_mps` lists, then checking that a single valid parse exists, this PR introduces a `check_for_ambiguity()` method that gets called as soon as the relevant `MatcherLoc` is observed. `check_for_ambiguity()` immediately drains `cur_mps` instead of waiting for the outer loop to do so, and evaluates the mps within a "checking for ambiguity" context.

This change was complicated by the fact that `bb_mps` was relied on for error messages; it was passed along to `Tracker::ambiguity()`. The same is true for `next_mps`. The first few commits of this PR (after pending rebases) add state to `Tracker` so that it can compute the relevant diagnostic information independently of `bb_mps`.

This PR complicates the control flow around `parse_tt_inner()` in subtle ways. I'm not super happy about it, but I think it will become easier to understand again once a DFS approach is implemented.

~This PR contains #158894 and #158974. I'll rebase on top of `main` once they're both merged.~

Best reviewed commit-by-commit.

r? @nnethercote

Eagerly check for ambiguity in macro parsing

This PR implements an important step leading up to the BFS->DFS change: it makes ambiguity detection (as occurs when parsing meta-variables and reaching EOF) eager. Rather than accumulating the `bb_mps` and `eof_mps` lists, then checking that a single valid parse exists, this PR introduces a `check_for_ambiguity()` method that gets called as soon as the relevant `MatcherLoc` is observed. `check_for_ambiguity()` immediately drains `cur_mps` instead of waiting for the outer loop to do so, and evaluates the mps within a "checking for ambiguity" context.

This change was complicated by the fact that `bb_mps` was relied on for error messages; it was passed along to `Tracker::ambiguity()`. The same is true for `next_mps`. The first few commits of this PR (after pending rebases) add state to `Tracker` so that it can compute the relevant diagnostic information independently of `bb_mps`.

This PR complicates the control flow around `parse_tt_inner()` in subtle ways. I'm not super happy about it, but I think it will become easier to understand again once a DFS approach is implemented.

~This PR contains rust-lang/rust#158894 and rust-lang/rust#158974. I'll rebase on top of `main` once they're both merged.~

Best reviewed commit-by-commit.

r? @nnethercote

Rollup of 23 pull requests

Successful merges:

 - rust-lang/rust#158968 (stdarch subtree update)
 - rust-lang/rust#154445 (rustdoc: Represent `--output-format=json` coverage and ir differently)
 - rust-lang/rust#158495 (Rename HAS_CT_PROJECTION to HAS_CONST_ALIAS)
 - rust-lang/rust#158666 (Carry the `b_offset` inside `BackendRepr::ScalarPair`)
 - rust-lang/rust#158870 (std: merge the unix-like io::error modules into one file)
 - rust-lang/rust#158920 (Update wasm-component-ld to 0.5.26)
 - rust-lang/rust#158926 (wrapping_sh* methods: clarify underspecified reference)
 - rust-lang/rust#158927 (add core test run with `-Zforce-intrinsic-fallback`)
 - rust-lang/rust#158932 (Do not build the compiler when invoking `x perf compare`)
 - rust-lang/rust#158937 (Emit the emscripten entry point as `__main_argc_argv`)
 - rust-lang/rust#151379 (Stabilize `VecDeque::retain_back` from `truncate_front`)
 - rust-lang/rust#156144 (Better docs for PartialEq (includes macro rename))
 - rust-lang/rust#156548 ( Library support for aarch64-unknown-linux-pauthtest target)
 - rust-lang/rust#157995 (`Vec::dedup_by` docs explicit function argument order)
 - rust-lang/rust#158307 (CI job for parallel frontend ui tests)
 - rust-lang/rust#158741 (Simplify `Option::into_flat_iter` signature)
 - rust-lang/rust#158807 (Add regression test for CString::clone_into unwind safety)
 - rust-lang/rust#158862 (Fix the span for parameter suggestion )
 - rust-lang/rust#158894 (Make the ordering of non-terminal binds in ambiguity error messages deterministic)
 - rust-lang/rust#158902 (add codegen test for range length bound propagation)
 - rust-lang/rust#158913 (Update `browser-ui-test` version to `0.24.1`)
 - rust-lang/rust#158935 (std: support real fd methods on Emscripten)
 - rust-lang/rust#158978 (Add regression test for too-big by-value ABI args)

Eagerly check for ambiguity in macro parsing

This PR implements an important step leading up to the BFS->DFS change: it makes ambiguity detection (as occurs when parsing meta-variables and reaching EOF) eager. Rather than accumulating the `bb_mps` and `eof_mps` lists, then checking that a single valid parse exists, this PR introduces a `check_for_ambiguity()` method that gets called as soon as the relevant `MatcherLoc` is observed. `check_for_ambiguity()` immediately drains `cur_mps` instead of waiting for the outer loop to do so, and evaluates the mps within a "checking for ambiguity" context.

This change was complicated by the fact that `bb_mps` was relied on for error messages; it was passed along to `Tracker::ambiguity()`. The same is true for `next_mps`. The first few commits of this PR (after pending rebases) add state to `Tracker` so that it can compute the relevant diagnostic information independently of `bb_mps`.

This PR complicates the control flow around `parse_tt_inner()` in subtle ways. I'm not super happy about it, but I think it will become easier to understand again once a DFS approach is implemented.

~This PR contains rust-lang/rust#158894 and rust-lang/rust#158974. I'll rebase on top of `main` once they're both merged.~

Best reviewed commit-by-commit.

r? @nnethercote

Rollup of 23 pull requests

Successful merges:

 - rust-lang/rust#158968 (stdarch subtree update)
 - rust-lang/rust#154445 (rustdoc: Represent `--output-format=json` coverage and ir differently)
 - rust-lang/rust#158495 (Rename HAS_CT_PROJECTION to HAS_CONST_ALIAS)
 - rust-lang/rust#158666 (Carry the `b_offset` inside `BackendRepr::ScalarPair`)
 - rust-lang/rust#158870 (std: merge the unix-like io::error modules into one file)
 - rust-lang/rust#158920 (Update wasm-component-ld to 0.5.26)
 - rust-lang/rust#158926 (wrapping_sh* methods: clarify underspecified reference)
 - rust-lang/rust#158927 (add core test run with `-Zforce-intrinsic-fallback`)
 - rust-lang/rust#158932 (Do not build the compiler when invoking `x perf compare`)
 - rust-lang/rust#158937 (Emit the emscripten entry point as `__main_argc_argv`)
 - rust-lang/rust#151379 (Stabilize `VecDeque::retain_back` from `truncate_front`)
 - rust-lang/rust#156144 (Better docs for PartialEq (includes macro rename))
 - rust-lang/rust#156548 ( Library support for aarch64-unknown-linux-pauthtest target)
 - rust-lang/rust#157995 (`Vec::dedup_by` docs explicit function argument order)
 - rust-lang/rust#158307 (CI job for parallel frontend ui tests)
 - rust-lang/rust#158741 (Simplify `Option::into_flat_iter` signature)
 - rust-lang/rust#158807 (Add regression test for CString::clone_into unwind safety)
 - rust-lang/rust#158862 (Fix the span for parameter suggestion )
 - rust-lang/rust#158894 (Make the ordering of non-terminal binds in ambiguity error messages deterministic)
 - rust-lang/rust#158902 (add codegen test for range length bound propagation)
 - rust-lang/rust#158913 (Update `browser-ui-test` version to `0.24.1`)
 - rust-lang/rust#158935 (std: support real fd methods on Emscripten)
 - rust-lang/rust#158978 (Add regression test for too-big by-value ABI args)