diff --git a/compiler/rustc_lint/messages.ftl b/compiler/rustc_lint/messages.ftl index 79d529143811e..7d7b97e2eb1a3 100644 --- a/compiler/rustc_lint/messages.ftl +++ b/compiler/rustc_lint/messages.ftl @@ -403,8 +403,9 @@ lint_inner_macro_attribute_unstable = inner macro attributes are unstable lint_invalid_asm_label_binary = avoid using labels containing only the digits `0` and `1` in inline assembly .label = use a different label that doesn't start with `0` or `1` - .note = an LLVM bug makes these labels ambiguous with a binary literal number - .note = see for more information + .help = start numbering with `2` instead + .note1 = an LLVM bug makes these labels ambiguous with a binary literal number on x86 + .note2 = see for more information lint_invalid_asm_label_format_arg = avoid using named labels in inline assembly .help = only local labels of the form `:` should be used in inline asm diff --git a/compiler/rustc_lint/src/builtin.rs b/compiler/rustc_lint/src/builtin.rs index 485c214ac9def..9ebada0fff377 100644 --- a/compiler/rustc_lint/src/builtin.rs +++ b/compiler/rustc_lint/src/builtin.rs @@ -66,6 +66,7 @@ use rustc_span::source_map::Spanned; use rustc_span::symbol::{kw, sym, Ident, Symbol}; use rustc_span::{BytePos, InnerSpan, Span}; use rustc_target::abi::Abi; +use rustc_target::asm::InlineAsmArch; use rustc_trait_selection::infer::{InferCtxtExt, TyCtxtInferExt}; use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt as _; use rustc_trait_selection::traits::{self, misc::type_allowed_to_implement_copy}; @@ -2739,8 +2740,9 @@ declare_lint! { /// /// ### Example /// - /// ```rust,compile_fail - /// # #![feature(asm_experimental_arch)] + /// ```rust,ignore (fails on non-x86_64) + /// #![cfg(target_arch = "x86_64")] + /// /// use std::arch::asm; /// /// fn main() { @@ -2750,19 +2752,32 @@ declare_lint! { /// } /// ``` /// - /// {{produces}} + /// This will produce: + /// + /// ```text + /// error: avoid using labels containing only the digits `0` and `1` in inline assembly + /// --> :7:15 + /// | + /// 7 | asm!("0: jmp 0b"); + /// | ^ use a different label that doesn't start with `0` or `1` + /// | + /// = help: start numbering with `2` instead + /// = note: an LLVM bug makes these labels ambiguous with a binary literal number on x86 + /// = note: see for more information + /// = note: `#[deny(binary_asm_labels)]` on by default + /// ``` /// /// ### Explanation /// - /// A [LLVM bug] causes this code to fail to compile because it interprets the `0b` as a binary - /// literal instead of a reference to the previous local label `0`. Note that even though the - /// bug is marked as fixed, it only fixes a specific usage of intel syntax within standalone - /// files, not inline assembly. To work around this bug, don't use labels that could be - /// confused with a binary literal. + /// An [LLVM bug] causes this code to fail to compile because it interprets the `0b` as a binary + /// literal instead of a reference to the previous local label `0`. To work around this bug, + /// don't use labels that could be confused with a binary literal. + /// + /// This behavior is platform-specific to x86 and x86-64. /// /// See the explanation in [Rust By Example] for more details. /// - /// [LLVM bug]: https://bugs.llvm.org/show_bug.cgi?id=36144 + /// [LLVM bug]: https://github.com/llvm/llvm-project/issues/99547 /// [Rust By Example]: https://doc.rust-lang.org/nightly/rust-by-example/unsafe/asm.html#labels pub BINARY_ASM_LABELS, Deny, @@ -2908,16 +2923,22 @@ impl<'tcx> LateLintPass<'tcx> for AsmLabels { InvalidAsmLabel::FormatArg { missing_precise_span }, ); } - AsmLabelKind::Binary => { - // the binary asm issue only occurs when using intel syntax - if !options.contains(InlineAsmOptions::ATT_SYNTAX) { - cx.emit_span_lint( - BINARY_ASM_LABELS, - span, - InvalidAsmLabel::Binary { missing_precise_span, span }, - ) - } + // the binary asm issue only occurs when using intel syntax on x86 targets + AsmLabelKind::Binary + if !options.contains(InlineAsmOptions::ATT_SYNTAX) + && matches!( + cx.tcx.sess.asm_arch, + Some(InlineAsmArch::X86 | InlineAsmArch::X86_64) | None + ) => + { + cx.emit_span_lint( + BINARY_ASM_LABELS, + span, + InvalidAsmLabel::Binary { missing_precise_span, span }, + ) } + // No lint on anything other than x86 + AsmLabelKind::Binary => (), }; } } diff --git a/compiler/rustc_lint/src/lints.rs b/compiler/rustc_lint/src/lints.rs index ac5511faf1961..6c5f366727f95 100644 --- a/compiler/rustc_lint/src/lints.rs +++ b/compiler/rustc_lint/src/lints.rs @@ -2074,7 +2074,9 @@ pub enum InvalidAsmLabel { missing_precise_span: bool, }, #[diag(lint_invalid_asm_label_binary)] - #[note] + #[help] + #[note(lint_note1)] + #[note(lint_note2)] Binary { #[note(lint_invalid_asm_label_no_span)] missing_precise_span: bool, diff --git a/tests/ui/asm/binary_asm_labels.stderr b/tests/ui/asm/binary_asm_labels.stderr index 1f2943084f1eb..206d2da177982 100644 --- a/tests/ui/asm/binary_asm_labels.stderr +++ b/tests/ui/asm/binary_asm_labels.stderr @@ -4,7 +4,9 @@ error: avoid using labels containing only the digits `0` and `1` in inline assem LL | asm!("0: jmp 0b"); | ^ use a different label that doesn't start with `0` or `1` | - = note: an LLVM bug makes these labels ambiguous with a binary literal number + = help: start numbering with `2` instead + = note: an LLVM bug makes these labels ambiguous with a binary literal number on x86 + = note: see for more information = note: `#[deny(binary_asm_labels)]` on by default error: avoid using labels containing only the digits `0` and `1` in inline assembly @@ -13,7 +15,9 @@ error: avoid using labels containing only the digits `0` and `1` in inline assem LL | asm!("1: jmp 1b"); | ^ use a different label that doesn't start with `0` or `1` | - = note: an LLVM bug makes these labels ambiguous with a binary literal number + = help: start numbering with `2` instead + = note: an LLVM bug makes these labels ambiguous with a binary literal number on x86 + = note: see for more information error: avoid using labels containing only the digits `0` and `1` in inline assembly --> $DIR/binary_asm_labels.rs:13:15 @@ -21,7 +25,9 @@ error: avoid using labels containing only the digits `0` and `1` in inline assem LL | asm!("10: jmp 10b"); | ^^ use a different label that doesn't start with `0` or `1` | - = note: an LLVM bug makes these labels ambiguous with a binary literal number + = help: start numbering with `2` instead + = note: an LLVM bug makes these labels ambiguous with a binary literal number on x86 + = note: see for more information error: avoid using labels containing only the digits `0` and `1` in inline assembly --> $DIR/binary_asm_labels.rs:14:15 @@ -29,7 +35,9 @@ error: avoid using labels containing only the digits `0` and `1` in inline assem LL | asm!("01: jmp 01b"); | ^^ use a different label that doesn't start with `0` or `1` | - = note: an LLVM bug makes these labels ambiguous with a binary literal number + = help: start numbering with `2` instead + = note: an LLVM bug makes these labels ambiguous with a binary literal number on x86 + = note: see for more information error: avoid using labels containing only the digits `0` and `1` in inline assembly --> $DIR/binary_asm_labels.rs:15:15 @@ -37,7 +45,9 @@ error: avoid using labels containing only the digits `0` and `1` in inline assem LL | asm!("1001101: jmp 1001101b"); | ^^^^^^^ use a different label that doesn't start with `0` or `1` | - = note: an LLVM bug makes these labels ambiguous with a binary literal number + = help: start numbering with `2` instead + = note: an LLVM bug makes these labels ambiguous with a binary literal number on x86 + = note: see for more information error: aborting due to 5 previous errors diff --git a/tests/ui/asm/binary_asm_labels_allowed.rs b/tests/ui/asm/binary_asm_labels_allowed.rs new file mode 100644 index 0000000000000..a21ab8d70f5b4 --- /dev/null +++ b/tests/ui/asm/binary_asm_labels_allowed.rs @@ -0,0 +1,17 @@ +//@ build-pass +//@ only-aarch64 + +// The `binary_asm_labels` lint should only be raised on `x86`. Make sure it +// doesn't get raised on other platforms. + +use std::arch::asm; + +fn main() { + unsafe { + asm!("0: bl 0b"); + asm!("1: bl 1b"); + asm!("10: bl 10b"); + asm!("01: bl 01b"); + asm!("1001101: bl 1001101b"); + } +}