Implement unused assignments lints on HIR #4285
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CohenArthur
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This is really good work, well done!!!
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This change moves the unused variable checker from the type resolver to HIR. We can now use the HIR Default Visitor, and it will be much more easier to implement other unused lints with this change. gcc/rust/ChangeLog: * Make-lang.in: Add new files rules in Makefile. * lang.opt: Add new flag. * rust-session-manager.cc (Session::compile_crate): Execute new variable checker. * checks/lints/unused-var/rust-unused-var-checker.cc (UnusedVarChecker): Implement unused variable checker. * checks/lints/unused-var/rust-unused-var-checker.h (UnusedVarChecker): Implement unused variable checker. * checks/lints/unused-var/rust-unused-var-collector.cc (UnusedVarCollector): Implement unused variable collector. * checks/lints/unused-var/rust-unused-var-collector.h (UnusedVarCollector): Implement unused variable collector. * checks/lints/unused-var/rust-unused-var-context.cc (UnusedVarContext): Implement unused variable context. * checks/lints/unused-var/rust-unused-var-context.h (UnusedVarContext): Implement unused variable context. gcc/testsuite/ChangeLog: * rust/compile/static_item_0.rs: New test. * rust/compile/template_function_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): 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 #4055
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)