diff --git a/compiler/rustc_const_eval/src/const_eval/machine.rs b/compiler/rustc_const_eval/src/const_eval/machine.rs index f16aea6f34b75..6c92ad45f479f 100644 --- a/compiler/rustc_const_eval/src/const_eval/machine.rs +++ b/compiler/rustc_const_eval/src/const_eval/machine.rs @@ -207,7 +207,7 @@ impl<'mir, 'tcx: 'mir> CompileTimeEvalContext<'mir, 'tcx> { ) -> InterpResult<'tcx, Option>> { let def_id = instance.def_id(); - if Some(def_id) == self.tcx.lang_items().panic_display() + if self.tcx.has_attr(def_id, sym::rustc_const_panic_str) || Some(def_id) == self.tcx.lang_items().begin_panic_fn() { let args = self.copy_fn_args(args)?; diff --git a/compiler/rustc_const_eval/src/transform/check_consts/check.rs b/compiler/rustc_const_eval/src/transform/check_consts/check.rs index f288ddc25d3a4..97c3a7d5b8d41 100644 --- a/compiler/rustc_const_eval/src/transform/check_consts/check.rs +++ b/compiler/rustc_const_eval/src/transform/check_consts/check.rs @@ -886,7 +886,7 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { // At this point, we are calling a function, `callee`, whose `DefId` is known... - // `begin_panic` and `panic_display` are generic functions that accept + // `begin_panic` and `#[rustc_const_panic_str]` functions accept generic // types other than str. Check to enforce that only str can be used in // const-eval. @@ -898,8 +898,8 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { } } - // const-eval of the `panic_display` fn assumes the argument is `&&str` - if Some(callee) == tcx.lang_items().panic_display() { + // const-eval of `#[rustc_const_panic_str]` functions assumes the argument is `&&str` + if tcx.has_attr(callee, sym::rustc_const_panic_str) { match args[0].ty(&self.ccx.body.local_decls, tcx).kind() { ty::Ref(_, ty, _) if matches!(ty.kind(), ty::Ref(_, ty, _) if ty.is_str()) => { diff --git a/compiler/rustc_feature/src/builtin_attrs.rs b/compiler/rustc_feature/src/builtin_attrs.rs index 04ebe22a9eb8a..bd0dffeb127ef 100644 --- a/compiler/rustc_feature/src/builtin_attrs.rs +++ b/compiler/rustc_feature/src/builtin_attrs.rs @@ -667,6 +667,10 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[ rustc_attr!( rustc_do_not_const_check, Normal, template!(Word), WarnFollowing, INTERNAL_UNSTABLE ), + // Ensure the argument to this function is &&str during const-check. + rustc_attr!( + rustc_const_panic_str, Normal, template!(Word), WarnFollowing, INTERNAL_UNSTABLE + ), // ========================================================================== // Internal attributes, Layout related: diff --git a/compiler/rustc_hir/src/lang_items.rs b/compiler/rustc_hir/src/lang_items.rs index 23b20543d5355..4a89a6f7e3926 100644 --- a/compiler/rustc_hir/src/lang_items.rs +++ b/compiler/rustc_hir/src/lang_items.rs @@ -230,7 +230,6 @@ language_item_table! { Panic, sym::panic, panic_fn, Target::Fn, GenericRequirement::Exact(0); PanicNounwind, sym::panic_nounwind, panic_nounwind, Target::Fn, GenericRequirement::Exact(0); PanicFmt, sym::panic_fmt, panic_fmt, Target::Fn, GenericRequirement::None; - PanicDisplay, sym::panic_display, panic_display, Target::Fn, GenericRequirement::None; ConstPanicFmt, sym::const_panic_fmt, const_panic_fmt, Target::Fn, GenericRequirement::None; PanicBoundsCheck, sym::panic_bounds_check, panic_bounds_check_fn, Target::Fn, GenericRequirement::Exact(0); PanicMisalignedPointerDereference, sym::panic_misaligned_pointer_dereference, panic_misaligned_pointer_dereference_fn, Target::Fn, GenericRequirement::Exact(0); diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs index 382754be2ca83..b23895a54863b 100644 --- a/compiler/rustc_span/src/symbol.rs +++ b/compiler/rustc_span/src/symbol.rs @@ -1104,7 +1104,6 @@ symbols! { panic_abort, panic_bounds_check, panic_cannot_unwind, - panic_display, panic_fmt, panic_handler, panic_impl, @@ -1299,6 +1298,7 @@ symbols! { rustc_coherence_is_core, rustc_coinductive, rustc_confusables, + rustc_const_panic_str, rustc_const_stable, rustc_const_unstable, rustc_conversion_suggestion, diff --git a/library/core/src/panic.rs b/library/core/src/panic.rs index 20be60d35353e..02974b0ec147c 100644 --- a/library/core/src/panic.rs +++ b/library/core/src/panic.rs @@ -47,6 +47,7 @@ pub macro panic_2015 { #[allow_internal_unstable(core_panic, const_format_args)] #[rustc_diagnostic_item = "core_panic_2021_macro"] #[rustc_macro_transparency = "semitransparent"] +#[cfg(any(bootstrap, feature = "panic_immediate_abort"))] pub macro panic_2021 { () => ( $crate::panicking::panic("explicit panic") @@ -62,6 +63,50 @@ pub macro panic_2021 { }), } +#[doc(hidden)] +#[unstable(feature = "edition_panic", issue = "none", reason = "use panic!() instead")] +#[allow_internal_unstable( + core_panic, + core_intrinsics, + const_dispatch, + const_eval_select, + const_format_args, + rustc_attrs +)] +#[rustc_diagnostic_item = "core_panic_2021_macro"] +#[rustc_macro_transparency = "semitransparent"] +#[cfg(not(any(bootstrap, feature = "panic_immediate_abort")))] +pub macro panic_2021 { + () => ({ + // Create a function so that the argument for `track_caller` + // can be moved inside if possible. + #[cold] + #[track_caller] + #[inline(never)] + const fn panic_cold_explicit() -> ! { + $crate::panicking::panic_explicit() + } + panic_cold_explicit(); + }), + // Special-case the single-argument case for const_panic. + ("{}", $arg:expr $(,)?) => ({ + #[cold] + #[track_caller] + #[inline(never)] + #[rustc_const_panic_str] // enforce a &&str argument in const-check and hook this by const-eval + #[rustc_do_not_const_check] // hooked by const-eval + const fn panic_cold_display(arg: &T) -> ! { + $crate::panicking::panic_display(arg) + } + panic_cold_display(&$arg); + }), + ($($t:tt)+) => ({ + // Semicolon to prevent temporaries inside the formatting machinery from + // being considered alive in the caller after the panic_fmt call. + $crate::panicking::panic_fmt($crate::const_format_args!($($t)+)); + }), +} + #[doc(hidden)] #[unstable(feature = "edition_panic", issue = "none", reason = "use unreachable!() instead")] #[allow_internal_unstable(core_panic)] diff --git a/library/core/src/panicking.rs b/library/core/src/panicking.rs index 281f8c1e1663c..46f1c275b6ebb 100644 --- a/library/core/src/panicking.rs +++ b/library/core/src/panicking.rs @@ -152,6 +152,14 @@ pub const fn panic_str(expr: &str) -> ! { panic_display(&expr); } +#[track_caller] +#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never), cold)] +#[cfg_attr(feature = "panic_immediate_abort", inline)] +#[rustc_const_unstable(feature = "core_panic", issue = "none")] +pub const fn panic_explicit() -> ! { + panic_display(&"explicit panic"); +} + #[inline] #[track_caller] #[rustc_diagnostic_item = "unreachable_display"] // needed for `non-fmt-panics` lint @@ -161,8 +169,10 @@ pub fn unreachable_display(x: &T) -> ! { #[inline] #[track_caller] -#[lang = "panic_display"] // needed for const-evaluated panics #[rustc_do_not_const_check] // hooked by const-eval +#[cfg_attr(bootstrap, lang = "panic_display")] +// enforce a &&str argument in const-check and hook this by const-eval +#[cfg_attr(not(bootstrap), rustc_const_panic_str)] #[rustc_const_unstable(feature = "core_panic", issue = "none")] pub const fn panic_display(x: &T) -> ! { panic_fmt(format_args!("{}", *x)); diff --git a/src/tools/clippy/clippy_lints/src/mixed_read_write_in_expression.rs b/src/tools/clippy/clippy_lints/src/mixed_read_write_in_expression.rs index 367cd6bd41337..ea6a9bc5657da 100644 --- a/src/tools/clippy/clippy_lints/src/mixed_read_write_in_expression.rs +++ b/src/tools/clippy/clippy_lints/src/mixed_read_write_in_expression.rs @@ -134,15 +134,30 @@ impl<'a, 'tcx> DivergenceVisitor<'a, 'tcx> { } } +fn stmt_might_diverge(stmt: &Stmt<'_>) -> bool { + match stmt.kind { + StmtKind::Item(..) => false, + _ => true, + } +} + impl<'a, 'tcx> Visitor<'tcx> for DivergenceVisitor<'a, 'tcx> { fn visit_expr(&mut self, e: &'tcx Expr<'_>) { match e.kind { // fix #10776 ExprKind::Block(block, ..) => match (block.stmts, block.expr) { - ([], Some(e)) => self.visit_expr(e), - ([stmt], None) => match stmt.kind { - StmtKind::Expr(e) | StmtKind::Semi(e) => self.visit_expr(e), - _ => {}, + (stmts, Some(e)) => { + if stmts.iter().all(|stmt| !stmt_might_diverge(stmt)) { + self.visit_expr(e) + } + }, + ([first @ .., stmt], None) => { + if first.iter().all(|stmt| !stmt_might_diverge(stmt)) { + match stmt.kind { + StmtKind::Expr(e) | StmtKind::Semi(e) => self.visit_expr(e), + _ => {}, + } + } }, _ => {}, }, diff --git a/src/tools/clippy/clippy_utils/src/macros.rs b/src/tools/clippy/clippy_utils/src/macros.rs index 173f9841d4469..94334f55109b2 100644 --- a/src/tools/clippy/clippy_utils/src/macros.rs +++ b/src/tools/clippy/clippy_utils/src/macros.rs @@ -227,16 +227,26 @@ pub enum PanicExpn<'a> { impl<'a> PanicExpn<'a> { pub fn parse(expr: &'a Expr<'a>) -> Option { - let ExprKind::Call(callee, [arg, rest @ ..]) = &expr.kind else { + let ExprKind::Call(callee, args) = &expr.kind else { return None; }; let ExprKind::Path(QPath::Resolved(_, path)) = &callee.kind else { return None; }; - let result = match path.segments.last().unwrap().ident.as_str() { + let name = path.segments.last().unwrap().ident.as_str(); + + // This has no argument + if name == "panic_cold_explicit" { + return Some(Self::Empty); + }; + + let [arg, rest @ ..] = args else { + return None; + }; + let result = match name { "panic" if arg.span.ctxt() == expr.span.ctxt() => Self::Empty, "panic" | "panic_str" => Self::Str(arg), - "panic_display" => { + "panic_display" | "panic_cold_display" => { let ExprKind::AddrOf(_, _, e) = &arg.kind else { return None; }; diff --git a/src/tools/clippy/tests/ui/match_same_arms_non_exhaustive.rs b/src/tools/clippy/tests/ui/match_same_arms_non_exhaustive.rs index 1ee048bf7f6c3..e1b95aa577604 100644 --- a/src/tools/clippy/tests/ui/match_same_arms_non_exhaustive.rs +++ b/src/tools/clippy/tests/ui/match_same_arms_non_exhaustive.rs @@ -4,14 +4,18 @@ //@no-rustfix use std::sync::atomic::Ordering; // #[non_exhaustive] enum +fn repeat() -> ! { + panic!() +} + pub fn f(x: Ordering) { match x { Ordering::Relaxed => println!("relaxed"), Ordering::Release => println!("release"), Ordering::Acquire => println!("acquire"), - Ordering::AcqRel | Ordering::SeqCst => panic!(), + Ordering::AcqRel | Ordering::SeqCst => repeat(), #[deny(non_exhaustive_omitted_patterns)] - _ => panic!(), + _ => repeat(), } } @@ -25,8 +29,8 @@ mod f { Ordering::Relaxed => println!("relaxed"), Ordering::Release => println!("release"), Ordering::Acquire => println!("acquire"), - Ordering::AcqRel | Ordering::SeqCst => panic!(), - _ => panic!(), + Ordering::AcqRel | Ordering::SeqCst => repeat(), + _ => repeat(), } } } @@ -38,9 +42,9 @@ pub fn g(x: Ordering) { Ordering::Relaxed => println!("relaxed"), Ordering::Release => println!("release"), Ordering::Acquire => println!("acquire"), - Ordering::AcqRel | Ordering::SeqCst => panic!(), + Ordering::AcqRel | Ordering::SeqCst => repeat(), //~^ ERROR: this match arm has an identical body to the `_` wildcard arm - _ => panic!(), + _ => repeat(), } } @@ -52,9 +56,9 @@ mod g { Ordering::Relaxed => println!("relaxed"), Ordering::Release => println!("release"), Ordering::Acquire => println!("acquire"), - Ordering::AcqRel | Ordering::SeqCst => panic!(), + Ordering::AcqRel | Ordering::SeqCst => repeat(), //~^ ERROR: this match arm has an identical body to the `_` wildcard arm - _ => panic!(), + _ => repeat(), } } } diff --git a/src/tools/clippy/tests/ui/match_same_arms_non_exhaustive.stderr b/src/tools/clippy/tests/ui/match_same_arms_non_exhaustive.stderr index a039536338bcb..ae6b02ab1b507 100644 --- a/src/tools/clippy/tests/ui/match_same_arms_non_exhaustive.stderr +++ b/src/tools/clippy/tests/ui/match_same_arms_non_exhaustive.stderr @@ -1,29 +1,29 @@ error: this match arm has an identical body to the `_` wildcard arm - --> $DIR/match_same_arms_non_exhaustive.rs:41:9 + --> $DIR/match_same_arms_non_exhaustive.rs:45:9 | -LL | Ordering::AcqRel | Ordering::SeqCst => panic!(), +LL | Ordering::AcqRel | Ordering::SeqCst => repeat(), | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try removing the arm | = help: or try changing either arm body note: `_` wildcard arm here - --> $DIR/match_same_arms_non_exhaustive.rs:43:9 + --> $DIR/match_same_arms_non_exhaustive.rs:47:9 | -LL | _ => panic!(), +LL | _ => repeat(), | ^^^^^^^^^^^^^ = note: `-D clippy::match-same-arms` implied by `-D warnings` = help: to override `-D warnings` add `#[allow(clippy::match_same_arms)]` error: this match arm has an identical body to the `_` wildcard arm - --> $DIR/match_same_arms_non_exhaustive.rs:55:13 + --> $DIR/match_same_arms_non_exhaustive.rs:59:13 | -LL | Ordering::AcqRel | Ordering::SeqCst => panic!(), +LL | Ordering::AcqRel | Ordering::SeqCst => repeat(), | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try removing the arm | = help: or try changing either arm body note: `_` wildcard arm here - --> $DIR/match_same_arms_non_exhaustive.rs:57:13 + --> $DIR/match_same_arms_non_exhaustive.rs:61:13 | -LL | _ => panic!(), +LL | _ => repeat(), | ^^^^^^^^^^^^^ error: aborting due to 2 previous errors