fixed the duplicate metavariables issue#4444
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hriztam wants to merge 8 commits intoRust-GCC:masterfrom
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fixed the duplicate metavariables issue#4444hriztam wants to merge 8 commits intoRust-GCC:masterfrom
hriztam wants to merge 8 commits intoRust-GCC:masterfrom
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Addresses Rust-GCC#4409. Validate duplicate matcher bindings for `macro_rules!` during definition resolution so duplicates are diagnosed even if the macro is never invoked. gcc/rust/ChangeLog: * expand/rust-macro-expand.cc (MacroExpander::expand_decl_macro): Always emit the failed-to-match error when no rule matches. (MacroExpander::match_matcher): Remove duplicate-binding checks. * expand/rust-macro-expand.h (MacroExpander): Remove had_duplicate_error state. * resolve/rust-early-name-resolver-2.0.cc (check_matcher_for_duplicate_bindings): New helper. (Early::visit): Check for duplicate matcher bindings in macro definitions. gcc/testsuite/ChangeLog: * rust/compile/macros/mbe/macro-duplicate-binding.rs: Check duplicate matcher bindings on an unused macro definition.
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ok let me update the PR |
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Addresses #4409.
This change moves duplicate matcher binding validation for
macro_rules!from invocation-time matching into macro-definition validation during early name resolution. This makes duplicate metavariable bindings fail even when the macro is never invoked, matching rustc’s behavior forduplicate matcher binding.It also adds an unused macro-definition warning pass in expansion by scanning AST macro definitions and checking whether each definition is referenced by a resolved invocation (excluding builtins and
#[macro_export]cases), producingunused macro definition.The expander-side duplicate-binding guard logic was removed since diagnostics are now emitted at definition validation time.
Tests:
gcc/testsuite/rust/compile/macros/mbe/macro-duplicate-binding.rsto cover the uninvoked reproducer and assert both:duplicate matcher bindingerrorunused macro definitionwarningAlso I tried to format the code using clang-format but that resulted in a much larger pr with a lot of files formatted at once, so I reverted it for the time being. Let me know if that is something which is needed
Signed-off-by: Hritam Shrivastava hritamstark05@gmail.com