Implement declarative (macro_rules!) derive macros (RFC 3698)#145208
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(Removing T-clippy and T-rustdoc, because the two commits specific to this PR don't touch them.) |
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(Marking as "waiting on review" because I'm seeking help with the test failure here.) |
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(Marking for review now that 145153 is queued.) |
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(I'll wait until the rebase anyway.) |
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Rollup of 11 pull requests Successful merges: - #139345 (Extend `QueryStability` to handle `IntoIterator` implementations) - #144838 (Fix outdated doc comment) - #145206 (Port `#[custom_mir(..)]` to the new attribute system) - #145208 (Implement declarative (`macro_rules!`) derive macros (RFC 3698)) - #145309 (Fix `-Zregparm` for LLVM builtins) - #145355 (Add codegen test for issue 122734) - #145420 (cg_llvm: Use LLVM-C bindings for `LLVMSetTailCallKind`, `LLVMGetTypeKind`) - #145451 (Add static glibc to the nix dev shell) - #145460 (Speedup `copy_src_dirs` in bootstrap) - #145476 (Fix typo in doc for library/std/src/fs.rs#set_permissions) - #145485 (Fix deprecation attributes on foreign statics) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup of 11 pull requests Successful merges: - #139345 (Extend `QueryStability` to handle `IntoIterator` implementations) - #144838 (Fix outdated doc comment) - #145206 (Port `#[custom_mir(..)]` to the new attribute system) - #145208 (Implement declarative (`macro_rules!`) derive macros (RFC 3698)) - #145309 (Fix `-Zregparm` for LLVM builtins) - #145355 (Add codegen test for issue 122734) - #145420 (cg_llvm: Use LLVM-C bindings for `LLVMSetTailCallKind`, `LLVMGetTypeKind`) - #145451 (Add static glibc to the nix dev shell) - #145460 (Speedup `copy_src_dirs` in bootstrap) - #145476 (Fix typo in doc for library/std/src/fs.rs#set_permissions) - #145485 (Fix deprecation attributes on foreign statics) r? `@ghost` `@rustbot` modify labels: rollup
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…enkov Implement declarative (`macro_rules!`) derive macros (RFC 3698) This is a draft for review, and should not be merged yet. This is layered atop rust-lang#145153 , and has only two additional commits atop that. The first handles parsing and provides a test for various parse errors. The second implements expansion and handles application. This implements RFC 3698, "Declarative (`macro_rules!`) derive macros". Tracking issue: rust-lang#143549 This has one remaining issue, which I could use some help debugging: in `tests/ui/macros/macro-rules-derive-error.rs`, the diagnostics for `derive(fn_only)` (for a `fn_only` with no `derive` rules) and `derive(ForwardReferencedDerive)` both get emitted twice, as a duplicate diagnostic. From what I can tell via adding some debugging code, `unresolved_macro_suggestions` is getting called twice from `finalize_macro_resolutions` for each of them, because `self.single_segment_macro_resolutions` has two entries for the macro, with two different `parent_scope` values. I'm not clear on why that happened; it doesn't happen with the equivalent code using attrs. I'd welcome any suggestions for fixing this.
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Rollup of 10 pull requests Successful merges: - #140794 (Add information about group a lint belongs to) - #144476 (rustdoc-search: search backend with partitioned suffix tree) - #144838 (Fix outdated doc comment) - #145206 (Port `#[custom_mir(..)]` to the new attribute system) - #145208 (Implement declarative (`macro_rules!`) derive macros (RFC 3698)) - #145420 (cg_llvm: Use LLVM-C bindings for `LLVMSetTailCallKind`, `LLVMGetTypeKind`) - #145451 (Add static glibc to the nix dev shell) - #145460 (Speedup `copy_src_dirs` in bootstrap) - #145476 (Fix typo in doc for library/std/src/fs.rs#set_permissions) - #145485 (Fix deprecation attributes on foreign statics) r? `@ghost` `@rustbot` modify labels: rollup
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…enkov Implement declarative (`macro_rules!`) derive macros (RFC 3698) This is a draft for review, and should not be merged yet. This is layered atop rust-lang#145153 , and has only two additional commits atop that. The first handles parsing and provides a test for various parse errors. The second implements expansion and handles application. This implements RFC 3698, "Declarative (`macro_rules!`) derive macros". Tracking issue: rust-lang#143549 This has one remaining issue, which I could use some help debugging: in `tests/ui/macros/macro-rules-derive-error.rs`, the diagnostics for `derive(fn_only)` (for a `fn_only` with no `derive` rules) and `derive(ForwardReferencedDerive)` both get emitted twice, as a duplicate diagnostic. From what I can tell via adding some debugging code, `unresolved_macro_suggestions` is getting called twice from `finalize_macro_resolutions` for each of them, because `self.single_segment_macro_resolutions` has two entries for the macro, with two different `parent_scope` values. I'm not clear on why that happened; it doesn't happen with the equivalent code using attrs. I'd welcome any suggestions for fixing this.
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…enkov Implement declarative (`macro_rules!`) derive macros (RFC 3698) This is a draft for review, and should not be merged yet. This is layered atop rust-lang#145153 , and has only two additional commits atop that. The first handles parsing and provides a test for various parse errors. The second implements expansion and handles application. This implements RFC 3698, "Declarative (`macro_rules!`) derive macros". Tracking issue: rust-lang#143549 This has one remaining issue, which I could use some help debugging: in `tests/ui/macros/macro-rules-derive-error.rs`, the diagnostics for `derive(fn_only)` (for a `fn_only` with no `derive` rules) and `derive(ForwardReferencedDerive)` both get emitted twice, as a duplicate diagnostic. From what I can tell via adding some debugging code, `unresolved_macro_suggestions` is getting called twice from `finalize_macro_resolutions` for each of them, because `self.single_segment_macro_resolutions` has two entries for the macro, with two different `parent_scope` values. I'm not clear on why that happened; it doesn't happen with the equivalent code using attrs. I'd welcome any suggestions for fixing this.
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…enkov Implement declarative (`macro_rules!`) derive macros (RFC 3698) This is a draft for review, and should not be merged yet. This is layered atop rust-lang#145153 , and has only two additional commits atop that. The first handles parsing and provides a test for various parse errors. The second implements expansion and handles application. This implements RFC 3698, "Declarative (`macro_rules!`) derive macros". Tracking issue: rust-lang#143549 This has one remaining issue, which I could use some help debugging: in `tests/ui/macros/macro-rules-derive-error.rs`, the diagnostics for `derive(fn_only)` (for a `fn_only` with no `derive` rules) and `derive(ForwardReferencedDerive)` both get emitted twice, as a duplicate diagnostic. From what I can tell via adding some debugging code, `unresolved_macro_suggestions` is getting called twice from `finalize_macro_resolutions` for each of them, because `self.single_segment_macro_resolutions` has two entries for the macro, with two different `parent_scope` values. I'm not clear on why that happened; it doesn't happen with the equivalent code using attrs. I'd welcome any suggestions for fixing this.
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Rollup of 10 pull requests Successful merges: - #144476 (rustdoc-search: search backend with partitioned suffix tree) - #144838 (Fix outdated doc comment) - #145206 (Port `#[custom_mir(..)]` to the new attribute system) - #145208 (Implement declarative (`macro_rules!`) derive macros (RFC 3698)) - #145420 (cg_llvm: Use LLVM-C bindings for `LLVMSetTailCallKind`, `LLVMGetTypeKind`) - #145451 (Add static glibc to the nix dev shell) - #145460 (Speedup `copy_src_dirs` in bootstrap) - #145476 (Fix typo in doc for library/std/src/fs.rs#set_permissions) - #145485 (Fix deprecation attributes on foreign statics) - #145489 (library: Migrate from `cfg_if` to `cfg_select`) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup of 9 pull requests Successful merges: - #144476 (rustdoc-search: search backend with partitioned suffix tree) - #144838 (Fix outdated doc comment) - #145206 (Port `#[custom_mir(..)]` to the new attribute system) - #145208 (Implement declarative (`macro_rules!`) derive macros (RFC 3698)) - #145420 (cg_llvm: Use LLVM-C bindings for `LLVMSetTailCallKind`, `LLVMGetTypeKind`) - #145451 (Add static glibc to the nix dev shell) - #145460 (Speedup `copy_src_dirs` in bootstrap) - #145476 (Fix typo in doc for library/std/src/fs.rs#set_permissions) - #145485 (Fix deprecation attributes on foreign statics) r? `@ghost` `@rustbot` modify labels: rollup
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…enkov Implement declarative (`macro_rules!`) derive macros (RFC 3698) This is a draft for review, and should not be merged yet. This is layered atop rust-lang#145153 , and has only two additional commits atop that. The first handles parsing and provides a test for various parse errors. The second implements expansion and handles application. This implements RFC 3698, "Declarative (`macro_rules!`) derive macros". Tracking issue: rust-lang#143549 This has one remaining issue, which I could use some help debugging: in `tests/ui/macros/macro-rules-derive-error.rs`, the diagnostics for `derive(fn_only)` (for a `fn_only` with no `derive` rules) and `derive(ForwardReferencedDerive)` both get emitted twice, as a duplicate diagnostic. From what I can tell via adding some debugging code, `unresolved_macro_suggestions` is getting called twice from `finalize_macro_resolutions` for each of them, because `self.single_segment_macro_resolutions` has two entries for the macro, with two different `parent_scope` values. I'm not clear on why that happened; it doesn't happen with the equivalent code using attrs. I'd welcome any suggestions for fixing this.
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Rollup of 10 pull requests Successful merges: - #144838 (Fix outdated doc comment) - #145206 (Port `#[custom_mir(..)]` to the new attribute system) - #145208 (Implement declarative (`macro_rules!`) derive macros (RFC 3698)) - #145309 (Fix `-Zregparm` for LLVM builtins) - #145355 (Add codegen test for issue 122734) - #145420 (cg_llvm: Use LLVM-C bindings for `LLVMSetTailCallKind`, `LLVMGetTypeKind`) - #145451 (Add static glibc to the nix dev shell) - #145460 (Speedup `copy_src_dirs` in bootstrap) - #145476 (Fix typo in doc for library/std/src/fs.rs#set_permissions) - #145485 (Fix deprecation attributes on foreign statics) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup of 10 pull requests Successful merges: - #144838 (Fix outdated doc comment) - #145206 (Port `#[custom_mir(..)]` to the new attribute system) - #145208 (Implement declarative (`macro_rules!`) derive macros (RFC 3698)) - #145309 (Fix `-Zregparm` for LLVM builtins) - #145355 (Add codegen test for issue 122734) - #145420 (cg_llvm: Use LLVM-C bindings for `LLVMSetTailCallKind`, `LLVMGetTypeKind`) - #145451 (Add static glibc to the nix dev shell) - #145460 (Speedup `copy_src_dirs` in bootstrap) - #145476 (Fix typo in doc for library/std/src/fs.rs#set_permissions) - #145485 (Fix deprecation attributes on foreign statics) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup of 10 pull requests Successful merges: - #144838 (Fix outdated doc comment) - #145206 (Port `#[custom_mir(..)]` to the new attribute system) - #145208 (Implement declarative (`macro_rules!`) derive macros (RFC 3698)) - #145309 (Fix `-Zregparm` for LLVM builtins) - #145355 (Add codegen test for issue 122734) - #145420 (cg_llvm: Use LLVM-C bindings for `LLVMSetTailCallKind`, `LLVMGetTypeKind`) - #145451 (Add static glibc to the nix dev shell) - #145460 (Speedup `copy_src_dirs` in bootstrap) - #145476 (Fix typo in doc for library/std/src/fs.rs#set_permissions) - #145485 (Fix deprecation attributes on foreign statics) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup of 10 pull requests Successful merges: - #144838 (Fix outdated doc comment) - #145206 (Port `#[custom_mir(..)]` to the new attribute system) - #145208 (Implement declarative (`macro_rules!`) derive macros (RFC 3698)) - #145309 (Fix `-Zregparm` for LLVM builtins) - #145355 (Add codegen test for issue 122734) - #145420 (cg_llvm: Use LLVM-C bindings for `LLVMSetTailCallKind`, `LLVMGetTypeKind`) - #145451 (Add static glibc to the nix dev shell) - #145460 (Speedup `copy_src_dirs` in bootstrap) - #145476 (Fix typo in doc for library/std/src/fs.rs#set_permissions) - #145485 (Fix deprecation attributes on foreign statics) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of #145208 - joshtriplett:mbe-derive, r=petrochenkov Implement declarative (`macro_rules!`) derive macros (RFC 3698) This is a draft for review, and should not be merged yet. This is layered atop #145153 , and has only two additional commits atop that. The first handles parsing and provides a test for various parse errors. The second implements expansion and handles application. This implements RFC 3698, "Declarative (`macro_rules!`) derive macros". Tracking issue: #143549 This has one remaining issue, which I could use some help debugging: in `tests/ui/macros/macro-rules-derive-error.rs`, the diagnostics for `derive(fn_only)` (for a `fn_only` with no `derive` rules) and `derive(ForwardReferencedDerive)` both get emitted twice, as a duplicate diagnostic. From what I can tell via adding some debugging code, `unresolved_macro_suggestions` is getting called twice from `finalize_macro_resolutions` for each of them, because `self.single_segment_macro_resolutions` has two entries for the macro, with two different `parent_scope` values. I'm not clear on why that happened; it doesn't happen with the equivalent code using attrs. I'd welcome any suggestions for fixing this.
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…binarycat,mejrs rustdoc: properly support macros with multiple kinds Since it seems like I can't reopen #145458, opening this one. Although, it's the same PR minus the last new commit to handle a comment that was left unresolved in the original PR. All relevant details are still in the original PR though. It's an alternative (and likely a take-over) of #148005 since lang-team rejected the idea to add documentation on macro branches, making the multiple files approach less suitable. This implements #145153 in rustdoc. This PR voluntarily doesn't touch anything related to intra-doc links, I'll send a follow-up if needed. So now about the implementation itself: this is a weird case where a macro can be different things at once but still only gets one file generated. I saw two ways to implement this: 1. Handle `ItemKind::Macro` differently and iter through its `MacroKinds` values. 2. Add new placeholder variants in the `ItemKind` enum, which means that when we encounter them in rendering, we need to ignore them. It also makes the `ItemKind` enum bigger (and also needs more code to be handled). Another downside is that it needs to be handled in the JSON output. Now there was an interesting improvement that came with this PR in the `html::render::print_item::item_module` function: I simplified its implementation and split the different parts in a `HashMap` where the key is the item type. So then, we can just iterate through the keys and open/close the section at each iteration instead of keeping an `Option<section>` around. From RFCs: * #144579 * #145208 derive: <img width="442" height="327" alt="Screenshot From 2026-04-18 03-11-40" src="https://github.com/user-attachments/assets/f69587a0-8a2b-4080-bc8a-b63dd18f21c1" /> attr: <img width="442" height="327" alt="Screenshot From 2026-04-18 03-11-31" src="https://github.com/user-attachments/assets/bf9b235a-9d2f-435c-a91e-167562df6b68" /> both: <img width="442" height="327" alt="Screenshot From 2026-04-18 03-11-50" src="https://github.com/user-attachments/assets/b7e8b3c6-eb99-495b-bdf9-17ba8fb4da0d" /> r? @notriddle
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This implements RFC 3698, "Declarative (
macro_rules!) derive macros".Tracking issue: #143549
This has one remaining issue, which I could use some help debugging: in
tests/ui/macros/macro-rules-derive-error.rs, the diagnostics forderive(fn_only)(for afn_onlywith noderiverules) andderive(ForwardReferencedDerive)both get emitted twice, as a duplicatediagnostic.
From what I can tell via adding some debugging code,
unresolved_macro_suggestionsis getting called twice fromfinalize_macro_resolutionsfor each of them, becauseself.single_segment_macro_resolutionshas two entries for the macro, with twodifferent
parent_scopevalues. I'm not clear on why that happened; it doesn'thappen with the equivalent code using attrs.
I'd welcome any suggestions for fixing this.
macro_rules!) attribute macros (RFC 3697) #144579