diff --git a/compiler/rustc_hir_typeck/src/expr.rs b/compiler/rustc_hir_typeck/src/expr.rs index 2c28ffd1fe3df..a1a33885b944c 100644 --- a/compiler/rustc_hir_typeck/src/expr.rs +++ b/compiler/rustc_hir_typeck/src/expr.rs @@ -532,14 +532,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { ExprKind::Break(destination, ref expr_opt) => { self.check_expr_break(destination, expr_opt.as_deref(), expr) } - ExprKind::Continue(destination) => { - if destination.target_id.is_ok() { - tcx.types.never - } else { - // There was an error; make type-check fail. - Ty::new_misc_error(tcx) - } - } + ExprKind::Continue(destination) => self.check_expr_continue(destination, expr), ExprKind::Ret(ref expr_opt) => self.check_expr_return(expr_opt.as_deref(), expr), ExprKind::Become(call) => self.check_expr_become(call, expr), ExprKind::Let(let_expr) => self.check_expr_let(let_expr, expr.hir_id), @@ -989,6 +982,31 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { } } + fn check_expr_continue( + &self, + destination: hir::Destination, + expr: &'tcx hir::Expr<'tcx>, + ) -> Ty<'tcx> { + if let Ok(target_id) = destination.target_id { + if let hir::Node::Expr(hir::Expr { kind: ExprKind::Loop(..), .. }) = + self.tcx.hir_node(target_id) + { + self.tcx.types.never + } else { + // Liveness linting assumes `continue`s all point to loops. We'll report an error + // in `check_mod_loops`, but make sure we don't run liveness (#113379, #121623). + let guar = self.dcx().span_delayed_bug( + expr.span, + "found `continue` not pointing to loop, but no error reported", + ); + Ty::new_error(self.tcx, guar) + } + } else { + // There was an error; make type-check fail. + Ty::new_misc_error(self.tcx) + } + } + fn check_expr_return( &self, expr_opt: Option<&'tcx hir::Expr<'tcx>>, diff --git a/compiler/rustc_mir_build/src/builder/mod.rs b/compiler/rustc_mir_build/src/builder/mod.rs index 9cf051a8760be..8400709740f05 100644 --- a/compiler/rustc_mir_build/src/builder/mod.rs +++ b/compiler/rustc_mir_build/src/builder/mod.rs @@ -66,8 +66,7 @@ pub fn build_mir<'tcx>(tcx: TyCtxt<'tcx>, def: LocalDefId) -> Body<'tcx> { } }; - // this must run before MIR dump, because - // "not all control paths return a value" is reported here. + // Checking liveness after building the THIR ensures there were no typeck errors. // // maybe move the check to a MIR pass? tcx.ensure_ok().check_liveness(def); diff --git a/compiler/rustc_passes/src/liveness.rs b/compiler/rustc_passes/src/liveness.rs index 4e9b7fd44d4b8..763d9fda80494 100644 --- a/compiler/rustc_passes/src/liveness.rs +++ b/compiler/rustc_passes/src/liveness.rs @@ -122,7 +122,6 @@ enum LiveNodeKind { VarDefNode(Span, HirId), ClosureNode, ExitNode, - ErrNode, } fn live_node_kind_to_string(lnk: LiveNodeKind, tcx: TyCtxt<'_>) -> String { @@ -133,7 +132,6 @@ fn live_node_kind_to_string(lnk: LiveNodeKind, tcx: TyCtxt<'_>) -> String { VarDefNode(s, _) => format!("Var def node [{}]", sm.span_to_diagnostic_string(s)), ClosureNode => "Closure node".to_owned(), ExitNode => "Exit node".to_owned(), - ErrNode => "Error node".to_owned(), } } @@ -492,6 +490,9 @@ struct Liveness<'a, 'tcx> { impl<'a, 'tcx> Liveness<'a, 'tcx> { fn new(ir: &'a mut IrMaps<'tcx>, body_owner: LocalDefId) -> Liveness<'a, 'tcx> { let typeck_results = ir.tcx.typeck(body_owner); + // Liveness linting runs after building the THIR. We make several assumptions based on + // typeck succeeding, e.g. that breaks and continues are well-formed. + assert!(typeck_results.tainted_by_errors.is_none()); // FIXME(#132279): we're in a body here. let typing_env = ty::TypingEnv::non_body_analysis(ir.tcx, body_owner); let closure_min_captures = typeck_results.closure_min_captures.get(&body_owner); @@ -976,8 +977,9 @@ impl<'a, 'tcx> Liveness<'a, 'tcx> { // Now that we know the label we're going to, // look it up in the continue loop nodes table self.cont_ln.get(&sc).cloned().unwrap_or_else(|| { - self.ir.tcx.dcx().span_delayed_bug(expr.span, "continue to unknown label"); - self.ir.add_live_node(ErrNode) + // Liveness linting happens after building the THIR. Bad labels should already + // have been caught. + span_bug!(expr.span, "continue to unknown label"); }) } diff --git a/tests/crashes/113379.rs b/tests/crashes/113379.rs deleted file mode 100644 index 7163cbc39342d..0000000000000 --- a/tests/crashes/113379.rs +++ /dev/null @@ -1,7 +0,0 @@ -//@ known-bug: #113379 - -async fn f999() -> Vec { - 'b: { - continue 'b; - } -} diff --git a/tests/crashes/121623.rs b/tests/crashes/121623.rs deleted file mode 100644 index 3c01a7f452ca7..0000000000000 --- a/tests/crashes/121623.rs +++ /dev/null @@ -1,8 +0,0 @@ -//@ known-bug: #121623 -fn main() { - match () { - _ => 'b: { - continue 'b; - } - } -} diff --git a/tests/ui/label/continue-pointing-to-block-ice-113379.rs b/tests/ui/label/continue-pointing-to-block-ice-113379.rs new file mode 100644 index 0000000000000..8a6a9cc840986 --- /dev/null +++ b/tests/ui/label/continue-pointing-to-block-ice-113379.rs @@ -0,0 +1,12 @@ +//! Regression test for ICE #113379. Liveness linting assumes that `continue`s all point to loops. +//! This tests that if a `continue` points to a block, we don't run liveness lints. + +async fn f999() -> Vec { + //~^ ERROR `async fn` is not permitted in Rust 2015 + 'b: { + //~^ ERROR mismatched types + continue 'b; + //~^ ERROR `continue` pointing to a labeled block + } +} +//~^ ERROR `main` function not found diff --git a/tests/ui/label/continue-pointing-to-block-ice-113379.stderr b/tests/ui/label/continue-pointing-to-block-ice-113379.stderr new file mode 100644 index 0000000000000..ada6305ec999b --- /dev/null +++ b/tests/ui/label/continue-pointing-to-block-ice-113379.stderr @@ -0,0 +1,43 @@ +error[E0670]: `async fn` is not permitted in Rust 2015 + --> $DIR/continue-pointing-to-block-ice-113379.rs:4:1 + | +LL | async fn f999() -> Vec { + | ^^^^^ to use `async fn`, switch to Rust 2018 or later + | + = help: pass `--edition 2024` to `rustc` + = note: for more on editions, read https://doc.rust-lang.org/edition-guide + +error[E0601]: `main` function not found in crate `continue_pointing_to_block_ice_113379` + --> $DIR/continue-pointing-to-block-ice-113379.rs:11:2 + | +LL | } + | ^ consider adding a `main` function to `$DIR/continue-pointing-to-block-ice-113379.rs` + +error[E0696]: `continue` pointing to a labeled block + --> $DIR/continue-pointing-to-block-ice-113379.rs:8:9 + | +LL | / 'b: { +LL | | +LL | | continue 'b; + | | ^^^^^^^^^^^ labeled blocks cannot be `continue`'d +LL | | +LL | | } + | |_____- labeled block the `continue` points to + +error[E0308]: mismatched types + --> $DIR/continue-pointing-to-block-ice-113379.rs:6:5 + | +LL | / 'b: { +LL | | +LL | | continue 'b; +LL | | +LL | | } + | |_____^ expected `Vec`, found `()` + | + = note: expected struct `Vec` + found unit type `()` + +error: aborting due to 4 previous errors + +Some errors have detailed explanations: E0308, E0601, E0670, E0696. +For more information about an error, try `rustc --explain E0308`. diff --git a/tests/ui/label/continue-pointing-to-block-ice-121623.rs b/tests/ui/label/continue-pointing-to-block-ice-121623.rs new file mode 100644 index 0000000000000..7047f7a309aaf --- /dev/null +++ b/tests/ui/label/continue-pointing-to-block-ice-121623.rs @@ -0,0 +1,11 @@ +//! Regression test for ICE #121623. Liveness linting assumes that `continue`s all point to loops. +//! This tests that if a `continue` points to a block, we don't run liveness lints. + +fn main() { + match () { + _ => 'b: { + continue 'b; + //~^ ERROR `continue` pointing to a labeled block + } + } +} diff --git a/tests/ui/label/continue-pointing-to-block-ice-121623.stderr b/tests/ui/label/continue-pointing-to-block-ice-121623.stderr new file mode 100644 index 0000000000000..a484fb629d181 --- /dev/null +++ b/tests/ui/label/continue-pointing-to-block-ice-121623.stderr @@ -0,0 +1,14 @@ +error[E0696]: `continue` pointing to a labeled block + --> $DIR/continue-pointing-to-block-ice-121623.rs:7:13 + | +LL | _ => 'b: { + | ______________- +LL | | continue 'b; + | | ^^^^^^^^^^^ labeled blocks cannot be `continue`'d +LL | | +LL | | } + | |_________- labeled block the `continue` points to + +error: aborting due to 1 previous error + +For more information about this error, try `rustc --explain E0696`.