diff --git a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs index 821a9036654..f32ff57fe88 100644 --- a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs +++ b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs @@ -557,8 +557,8 @@ fn report_use_of_uninitialized( // for the branching codepaths that aren't covered, to point at them. let map = self.infcx.tcx.hir(); let body = map.body_owned_by(self.mir_def_id()); - - let mut visitor = ConditionVisitor { spans: &spans, name: &name, errors: vec![] }; + let mut visitor = + ConditionVisitor { tcx: self.infcx.tcx, spans: &spans, name: &name, errors: vec![] }; visitor.visit_body(&body); let mut show_assign_sugg = false; @@ -4372,13 +4372,14 @@ fn visit_expr(&mut self, ex: &'hir hir::Expr<'hir>) { /// Given a set of spans representing statements initializing the relevant binding, visit all the /// function expressions looking for branching code paths that *do not* initialize the binding. -struct ConditionVisitor<'b> { +struct ConditionVisitor<'b, 'tcx> { + tcx: TyCtxt<'tcx>, spans: &'b [Span], name: &'b str, errors: Vec<(Span, String)>, } -impl<'b, 'v> Visitor<'v> for ConditionVisitor<'b> { +impl<'b, 'v, 'tcx> Visitor<'v> for ConditionVisitor<'b, 'tcx> { fn visit_expr(&mut self, ex: &'v hir::Expr<'v>) { match ex.kind { hir::ExprKind::If(cond, body, None) => { @@ -4464,6 +4465,12 @@ fn visit_expr(&mut self, ex: &'v hir::Expr<'v>) { ), )); } else if let Some(guard) = &arm.guard { + if matches!( + self.tcx.hir_node(arm.body.hir_id), + hir::Node::Expr(hir::Expr { kind: hir::ExprKind::Ret(_), .. }) + ) { + continue; + } self.errors.push(( arm.pat.span.to(guard.span), format!( @@ -4473,6 +4480,12 @@ fn visit_expr(&mut self, ex: &'v hir::Expr<'v>) { ), )); } else { + if matches!( + self.tcx.hir_node(arm.body.hir_id), + hir::Node::Expr(hir::Expr { kind: hir::ExprKind::Ret(_), .. }) + ) { + continue; + } self.errors.push(( arm.pat.span, format!( diff --git a/tests/ui/borrowck/uninitalized-in-match-arm-issue-126133.rs b/tests/ui/borrowck/uninitalized-in-match-arm-issue-126133.rs new file mode 100644 index 00000000000..1974bbf9fe7 --- /dev/null +++ b/tests/ui/borrowck/uninitalized-in-match-arm-issue-126133.rs @@ -0,0 +1,22 @@ +enum E { + A, + B, + C, +} + +fn foo(e: E) { + let bar; + + match e { + E::A if true => return, + E::A => return, + E::B => {} + E::C => { + bar = 5; + } + } + + let _baz = bar; //~ ERROR E0381 +} + +fn main() {} diff --git a/tests/ui/borrowck/uninitalized-in-match-arm-issue-126133.stderr b/tests/ui/borrowck/uninitalized-in-match-arm-issue-126133.stderr new file mode 100644 index 00000000000..eb7d0f8b204 --- /dev/null +++ b/tests/ui/borrowck/uninitalized-in-match-arm-issue-126133.stderr @@ -0,0 +1,15 @@ +error[E0381]: used binding `bar` is possibly-uninitialized + --> $DIR/uninitalized-in-match-arm-issue-126133.rs:19:16 + | +LL | let bar; + | --- binding declared here but left uninitialized +... +LL | E::B => {} + | ---- if this pattern is matched, `bar` is not initialized +... +LL | let _baz = bar; + | ^^^ `bar` used here but it is possibly-uninitialized + +error: aborting due to 1 previous error + +For more information about this error, try `rustc --explain E0381`.