From 2668fa6ae1434973732c12fb8fba1516484a1091 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Le=C3=B3n=20Orell=20Valerian=20Liehr?= Date: Sat, 3 Feb 2024 17:34:25 +0100 Subject: [PATCH] Check for presence of field in typeck results before visiting it To prevent ICEs where the struct type is tainted by errors. Co-authored-by: Michael Goulet --- compiler/rustc_passes/src/dead.rs | 7 ++++++- .../field-access-after-const-eval-fail-in-ty.rs | 5 +++++ ...ld-access-after-const-eval-fail-in-ty.stderr | 17 +++++++++++++++++ 3 files changed, 28 insertions(+), 1 deletion(-) create mode 100644 tests/ui/consts/const-eval/field-access-after-const-eval-fail-in-ty.rs create mode 100644 tests/ui/consts/const-eval/field-access-after-const-eval-fail-in-ty.stderr diff --git a/compiler/rustc_passes/src/dead.rs b/compiler/rustc_passes/src/dead.rs index 9be286744351f..66d5d20a10938 100644 --- a/compiler/rustc_passes/src/dead.rs +++ b/compiler/rustc_passes/src/dead.rs @@ -464,7 +464,12 @@ impl<'tcx> Visitor<'tcx> for MarkSymbolVisitor<'tcx> { self.lookup_and_handle_method(expr.hir_id); } hir::ExprKind::Field(ref lhs, ..) => { - self.handle_field_access(lhs, expr.hir_id); + if self.typeck_results().opt_field_index(expr.hir_id).is_some() { + self.handle_field_access(lhs, expr.hir_id); + } else { + // The struct type is probably tainted by errors. + self.tcx.dcx().span_delayed_bug(expr.span, "couldn't resolve index for field"); + } } hir::ExprKind::Struct(qpath, fields, _) => { let res = self.typeck_results().qpath_res(qpath, expr.hir_id); diff --git a/tests/ui/consts/const-eval/field-access-after-const-eval-fail-in-ty.rs b/tests/ui/consts/const-eval/field-access-after-const-eval-fail-in-ty.rs new file mode 100644 index 0000000000000..3f1f208459d17 --- /dev/null +++ b/tests/ui/consts/const-eval/field-access-after-const-eval-fail-in-ty.rs @@ -0,0 +1,5 @@ +// Regression test for issue #120615. + +fn main() { + [(); loop {}].field; //~ ERROR constant evaluation is taking a long time +} diff --git a/tests/ui/consts/const-eval/field-access-after-const-eval-fail-in-ty.stderr b/tests/ui/consts/const-eval/field-access-after-const-eval-fail-in-ty.stderr new file mode 100644 index 0000000000000..9d62bbc2187f7 --- /dev/null +++ b/tests/ui/consts/const-eval/field-access-after-const-eval-fail-in-ty.stderr @@ -0,0 +1,17 @@ +error: constant evaluation is taking a long time + --> $DIR/field-access-after-const-eval-fail-in-ty.rs:4:10 + | +LL | [(); loop {}].field; + | ^^^^^^^ + | + = note: this lint makes sure the compiler doesn't get stuck due to infinite loops in const eval. + If your compilation actually takes a long time, you can safely allow the lint. +help: the constant being evaluated + --> $DIR/field-access-after-const-eval-fail-in-ty.rs:4:10 + | +LL | [(); loop {}].field; + | ^^^^^^^ + = note: `#[deny(long_running_const_eval)]` on by default + +error: aborting due to 1 previous error +