Implement unused assignments lints on HIR #4285
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This is really good work, well done!!!
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gcc/rust/ChangeLog: * checks/lints/unused-var/rust-unused-var-checker.cc (UnusedVarChecker): Implement unused assignments warning. (UnusedVarChecker::go): Remove unique pointer unused var context. (UnusedVarChecker::visit): Visit AssignExpr in HIR default visitor. * checks/lints/unused-var/rust-unused-var-checker.h: Add visit method. * checks/lints/unused-var/rust-unused-var-collector.cc (UnusedVarCollector): Collect warnings for assignments. (UnusedVarCollector::visit): Visit AssignExpr in HIR default visitor. * checks/lints/unused-var/rust-unused-var-collector.h: Add visit method. * checks/lints/unused-var/rust-unused-var-context.cc (UnusedVarContext::add_assign): Add assignment in map. (UnusedVarContext::remove_assign): Remove assignment in map. (UnusedVarContext::is_variable_assigned): Check if a variable is assigned. * checks/lints/unused-var/rust-unused-var-context.h: Add a map to stock assignments. gcc/testsuite/ChangeLog: * rust/compile/issue-4260_0.rs: New test. Signed-off-by: Lucas Ly Ba <lucas.ly-ba@outlook.com>
gcc/rust/ChangeLog: * checks/lints/unused-var/rust-unused-var-checker.cc (UnusedVarChecker::visit): Change unused name warning to unused variable warning. * checks/lints/unused-var/rust-unused-var-collector.cc (UnusedVarCollector::visit): Remove useless methods. * checks/lints/unused-var/rust-unused-var-collector.h: Same here. * checks/lints/unused-var/rust-unused-var-context.cc (UnusedVarContext::add_variable): Add used variables to set. (UnusedVarContext::mark_used): Remove method. (UnusedVarContext::is_variable_used): Check if the set contains the hir id linked to a variable. (UnusedVarContext::as_string): Refactor method for new set. * checks/lints/unused-var/rust-unused-var-context.h: Refactor methods. * lang.opt: Change description for unused check flag. gcc/testsuite/ChangeLog: * rust/compile/static_item_0.rs: Modify warning output. * rust/compile/template_function_0.rs: Modify warning output. Signed-off-by: Lucas Ly Ba <lucas.ly-ba@outlook.com>
gcc/rust/ChangeLog: * Make-lang.in: Compile the right files. * checks/lints/unused-var/rust-unused-var-checker.cc: Move to... * checks/lints/unused/rust-unused-checker.cc: ...here. * checks/lints/unused-var/rust-unused-var-checker.h: Move to... * checks/lints/unused/rust-unused-checker.h: ...here. * checks/lints/unused-var/rust-unused-var-collector.cc: Move to... * checks/lints/unused/rust-unused-collector.cc: ...here. * checks/lints/unused-var/rust-unused-var-collector.h: Move to... * checks/lints/unused/rust-unused-collector.h: ...here. * checks/lints/unused-var/rust-unused-var-context.cc: Move to... * checks/lints/unused/rust-unused-context.cc: ...here. * checks/lints/unused-var/rust-unused-var-context.h: Move to... * checks/lints/unused/rust-unused-context.h: ...here. * rust-session-manager.cc (Session::compile_crate): Call the right method. Signed-off-by: Lucas Ly Ba <lucas.ly-ba@outlook.com>
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Fixes #4260
on top of PR #4283 and PR #4331
Used the HIR default visitor for AssignExpr, added a map, to have all the unused assignments and attached some methods to it.
Since
is an HIR::PathInExpression we cannot visit the left expr of an assignment, because it would be considerered used. So I also added a walk_right to only visit the right expr.
( if we have a = b, we want to visit b)