diff --git a/compiler/rustc_lint/src/lib.rs b/compiler/rustc_lint/src/lib.rs index 196b8fd52d53f..2666212faaacf 100644 --- a/compiler/rustc_lint/src/lib.rs +++ b/compiler/rustc_lint/src/lib.rs @@ -597,6 +597,7 @@ fn register_internals(store: &mut LintStore) { "rustc::internal", None, vec![ + LintId::of(BROKEN_MIR), LintId::of(DEFAULT_HASH_TYPES), LintId::of(POTENTIAL_QUERY_INSTABILITY), LintId::of(USAGE_OF_TY_TYKIND), diff --git a/compiler/rustc_lint_defs/src/builtin.rs b/compiler/rustc_lint_defs/src/builtin.rs index 7172a47fb854d..54c4d4d43b285 100644 --- a/compiler/rustc_lint_defs/src/builtin.rs +++ b/compiler/rustc_lint_defs/src/builtin.rs @@ -3933,6 +3933,15 @@ declare_lint! { "`break` expression with label and unlabeled loop as value expression" } +crate::declare_tool_lint! { + /// The `broken_mir` statically detects undefined behaviour in the MIR optimization pipeline. + /// This is an internal lint, and not intended to be used directly. + pub rustc::BROKEN_MIR, + Deny, + "broken MIR", + report_in_external_macro: true +} + declare_lint! { /// The `non_exhaustive_omitted_patterns` lint aims to help consumers of a `#[non_exhaustive]` /// struct or enum who want to match all of its fields/variants explicitly. diff --git a/compiler/rustc_mir_transform/src/lint.rs b/compiler/rustc_mir_transform/src/lint.rs index 746068064b8fb..1b369fb6e1311 100644 --- a/compiler/rustc_mir_transform/src/lint.rs +++ b/compiler/rustc_mir_transform/src/lint.rs @@ -5,6 +5,7 @@ use std::borrow::Cow; use rustc_data_structures::fx::FxHashSet; +use rustc_hir::{HirId, CRATE_HIR_ID}; use rustc_index::bit_set::BitSet; use rustc_middle::mir::visit::{PlaceContext, Visitor}; use rustc_middle::mir::*; @@ -12,6 +13,7 @@ use rustc_middle::ty::TyCtxt; use rustc_mir_dataflow::impls::{MaybeStorageDead, MaybeStorageLive}; use rustc_mir_dataflow::storage::always_storage_live_locals; use rustc_mir_dataflow::{Analysis, ResultsCursor}; +use rustc_session::lint::builtin::BROKEN_MIR; pub fn lint_body<'tcx>(tcx: TyCtxt<'tcx>, body: &Body<'tcx>, when: String) { let always_live_locals = &always_storage_live_locals(body); @@ -30,6 +32,11 @@ pub fn lint_body<'tcx>(tcx: TyCtxt<'tcx>, body: &Body<'tcx>, when: String) { tcx, when, body, + lint_id: body + .source + .def_id() + .as_local() + .map_or(CRATE_HIR_ID, |def_id| tcx.local_def_id_to_hir_id(def_id)), is_fn_like: tcx.def_kind(body.source.def_id()).is_fn_like(), always_live_locals, maybe_storage_live, @@ -45,6 +52,7 @@ struct Lint<'a, 'tcx> { tcx: TyCtxt<'tcx>, when: String, body: &'a Body<'tcx>, + lint_id: HirId, is_fn_like: bool, always_live_locals: &'a BitSet, maybe_storage_live: ResultsCursor<'a, 'tcx, MaybeStorageLive<'a>>, @@ -53,19 +61,19 @@ struct Lint<'a, 'tcx> { } impl<'a, 'tcx> Lint<'a, 'tcx> { - #[track_caller] + #[allow(rustc::untranslatable_diagnostic)] + #[allow(rustc::diagnostic_outside_of_impl)] fn fail(&self, location: Location, msg: impl AsRef) { let span = self.body.source_info(location).span; - self.tcx.sess.dcx().span_delayed_bug( - span, - format!( + self.tcx.node_span_lint(BROKEN_MIR, self.lint_id, span, |lint| { + lint.primary_message(format!( "broken MIR in {:?} ({}) at {:?}:\n{}", self.body.source.instance, self.when, location, msg.as_ref() - ), - ); + )); + }); } } diff --git a/tests/mir-opt/reference_prop.rs b/tests/mir-opt/reference_prop.rs index 58d8b524ad642..7bc44cdac21f4 100644 --- a/tests/mir-opt/reference_prop.rs +++ b/tests/mir-opt/reference_prop.rs @@ -1,8 +1,7 @@ -//@ compile-flags: -Zlint-mir=no //@ test-mir-pass: ReferencePropagation //@ needs-unwind -#![feature(raw_ref_op)] +#![feature(raw_ref_op, lint_reasons)] #![feature(core_intrinsics, custom_mir)] #[inline(never)] @@ -678,6 +677,7 @@ fn read_through_raw(x: &mut usize) -> usize { } #[custom_mir(dialect = "runtime", phase = "post-cleanup")] +#[expect(rustc::broken_mir)] fn multiple_storage() { // CHECK-LABEL: multiple_storage // CHECK: _3 = (*_2); @@ -704,6 +704,7 @@ fn multiple_storage() { } #[custom_mir(dialect = "runtime", phase = "post-cleanup")] +#[expect(rustc::broken_mir)] fn dominate_storage() { // CHECK-LABEL: dominate_storage // CHECK: _5 = (*_2); @@ -734,6 +735,7 @@ fn dominate_storage() { } #[custom_mir(dialect = "runtime", phase = "post-cleanup")] +#[expect(rustc::broken_mir)] fn maybe_dead(m: bool) { // CHECK-LABEL: fn maybe_dead( // CHECK: (*_5) = const 7_i32; diff --git a/tests/ui/mir/lint/storage-live.rs b/tests/ui/mir/lint/storage-live.rs index ded02150342d5..0a20119a4b615 100644 --- a/tests/ui/mir/lint/storage-live.rs +++ b/tests/ui/mir/lint/storage-live.rs @@ -21,6 +21,7 @@ fn multiple_storage() { { StorageLive(a); StorageLive(a); + //~^ ERROR broken MIR Return() } } diff --git a/tests/ui/mir/lint/storage-live.stderr b/tests/ui/mir/lint/storage-live.stderr index 7d4c3f0832a97..1f6359daa79f9 100644 --- a/tests/ui/mir/lint/storage-live.stderr +++ b/tests/ui/mir/lint/storage-live.stderr @@ -5,14 +5,10 @@ error: internal compiler error: broken MIR in Item(DefId(0:8 ~ storage_live[HASH LL | StorageLive(a); | ^^^^^^^^^^^^^^ | -note: delayed at compiler/rustc_mir_transform/src/lint.rs:LL:CC - disabled backtrace - --> $DIR/storage-live.rs:23:13 - | -LL | StorageLive(a); - | ^^^^^^^^^^^^^^ - -aborting due to `-Z treat-err-as-bug=1` + = aborting due to `-Z treat-err-as-bug=1` error: the compiler unexpectedly panicked. this is a bug. query stack during panic: +#0 [mir_built] building MIR for `multiple_storage` +#1 [has_ffi_unwind_calls] checking if `multiple_storage` contains FFI-unwind calls end of query stack