diff --git a/Cargo.lock b/Cargo.lock index b98c4fd0642da..762f98cd4ac94 100644 --- a/Cargo.lock +++ b/Cargo.lock @@ -3453,6 +3453,7 @@ dependencies = [ "rustc_abi", "rustc_arena", "rustc_ast", + "rustc_ast_pretty", "rustc_attr", "rustc_data_structures", "rustc_errors", diff --git a/compiler/rustc_codegen_ssa/Cargo.toml b/compiler/rustc_codegen_ssa/Cargo.toml index b898cfec79669..01cf9369df7ea 100644 --- a/compiler/rustc_codegen_ssa/Cargo.toml +++ b/compiler/rustc_codegen_ssa/Cargo.toml @@ -17,6 +17,7 @@ regex = "1.4" rustc_abi = { path = "../rustc_abi" } rustc_arena = { path = "../rustc_arena" } rustc_ast = { path = "../rustc_ast" } +rustc_ast_pretty = { path = "../rustc_ast_pretty" } rustc_attr = { path = "../rustc_attr" } rustc_data_structures = { path = "../rustc_data_structures" } rustc_errors = { path = "../rustc_errors" } diff --git a/compiler/rustc_codegen_ssa/messages.ftl b/compiler/rustc_codegen_ssa/messages.ftl index 62db3d5a98cdd..56188714b44fd 100644 --- a/compiler/rustc_codegen_ssa/messages.ftl +++ b/compiler/rustc_codegen_ssa/messages.ftl @@ -201,6 +201,11 @@ codegen_ssa_missing_memory_ordering = Atomic intrinsic missing memory ordering codegen_ssa_missing_query_depgraph = found CGU-reuse attribute but `-Zquery-dep-graph` was not specified +codegen_ssa_mixed_export_name_and_no_mangle = `{$no_mangle_attr}` attribute may not be used in combination with `#[export_name]` + .label = `{$no_mangle_attr}` is ignored + .note = `#[export_name]` takes precedence + .suggestion = remove the `{$no_mangle_attr}` attribute + codegen_ssa_msvc_missing_linker = the msvc targets depend on the msvc linker but `link.exe` was not found codegen_ssa_multiple_external_func_decl = multiple declarations of external function `{$function}` from library `{$library_name}` have different calling conventions diff --git a/compiler/rustc_codegen_ssa/src/codegen_attrs.rs b/compiler/rustc_codegen_ssa/src/codegen_attrs.rs index 32e9422e005ab..59c543bb39785 100644 --- a/compiler/rustc_codegen_ssa/src/codegen_attrs.rs +++ b/compiler/rustc_codegen_ssa/src/codegen_attrs.rs @@ -3,11 +3,10 @@ use rustc_attr::{InlineAttr, InstructionSetAttr, OptimizeAttr, list_contains_nam use rustc_data_structures::fx::FxHashMap; use rustc_errors::codes::*; use rustc_errors::{DiagMessage, SubdiagMessage, struct_span_code_err}; -use rustc_hir as hir; use rustc_hir::def::DefKind; use rustc_hir::def_id::{DefId, LOCAL_CRATE, LocalDefId}; use rustc_hir::weak_lang_items::WEAK_LANG_ITEMS; -use rustc_hir::{LangItem, lang_items}; +use rustc_hir::{self as hir, HirId, LangItem, lang_items}; use rustc_middle::middle::codegen_fn_attrs::{ CodegenFnAttrFlags, CodegenFnAttrs, PatchableFunctionEntry, }; @@ -78,6 +77,7 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, did: LocalDefId) -> CodegenFnAttrs { let mut inline_span = None; let mut link_ordinal_span = None; let mut no_sanitize_span = None; + let mut mixed_export_name_no_mangle_lint_state = MixedExportNameAndNoMangleState::default(); for attr in attrs.iter() { // In some cases, attribute are only valid on functions, but it's the `check_attr` @@ -116,7 +116,12 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, did: LocalDefId) -> CodegenFnAttrs { sym::naked => codegen_fn_attrs.flags |= CodegenFnAttrFlags::NAKED, sym::no_mangle => { if tcx.opt_item_name(did.to_def_id()).is_some() { - codegen_fn_attrs.flags |= CodegenFnAttrFlags::NO_MANGLE + codegen_fn_attrs.flags |= CodegenFnAttrFlags::NO_MANGLE; + mixed_export_name_no_mangle_lint_state.track_no_mangle( + attr.span, + tcx.local_def_id_to_hir_id(did), + rustc_ast_pretty::pprust::attribute_to_string(attr), + ); } else { tcx.dcx() .struct_span_err( @@ -240,6 +245,7 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, did: LocalDefId) -> CodegenFnAttrs { .emit(); } codegen_fn_attrs.export_name = Some(s); + mixed_export_name_no_mangle_lint_state.track_export_name(attr.span); } } sym::target_feature => { @@ -513,6 +519,8 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, did: LocalDefId) -> CodegenFnAttrs { } } + mixed_export_name_no_mangle_lint_state.lint_if_mixed(tcx); + codegen_fn_attrs.inline = attrs.iter().fold(InlineAttr::None, |ia, attr| { if !attr.has_name(sym::inline) { return ia; @@ -779,6 +787,49 @@ fn check_link_name_xor_ordinal( } } +#[derive(Default)] +struct MixedExportNameAndNoMangleState { + export_name: Option, + hir_id: Option, + no_mangle: Option, + no_mangle_attr_name: Option, +} + +impl MixedExportNameAndNoMangleState { + fn track_export_name(&mut self, span: Span) { + self.export_name = Some(span); + } + + fn track_no_mangle(&mut self, span: Span, hir_id: HirId, attr_name: String) { + self.no_mangle = Some(span); + self.hir_id = Some(hir_id); + self.no_mangle_attr_name = Some(attr_name); + } + + /// Emit diagnostics if the lint condition is met. + fn lint_if_mixed(self, tcx: TyCtxt<'_>) { + if let Self { + export_name: Some(export_name), + no_mangle: Some(no_mangle), + hir_id: Some(hir_id), + no_mangle_attr_name: Some(no_mangle_attr_name), + } = self + { + tcx.emit_node_span_lint( + lint::builtin::UNUSED_ATTRIBUTES, + hir_id, + no_mangle, + errors::MixedExportNameAndNoMangle { + no_mangle, + no_mangle_attr: no_mangle_attr_name, + export_name, + removal_span: no_mangle, + }, + ); + } + } +} + pub(crate) fn provide(providers: &mut Providers) { *providers = Providers { codegen_fn_attrs, should_inherit_track_caller, ..*providers }; } diff --git a/compiler/rustc_codegen_ssa/src/errors.rs b/compiler/rustc_codegen_ssa/src/errors.rs index f93cb52ea3ea2..00f8654e670b1 100644 --- a/compiler/rustc_codegen_ssa/src/errors.rs +++ b/compiler/rustc_codegen_ssa/src/errors.rs @@ -10,7 +10,7 @@ use rustc_errors::codes::*; use rustc_errors::{ Diag, DiagArgValue, DiagCtxtHandle, Diagnostic, EmissionGuarantee, IntoDiagArg, Level, }; -use rustc_macros::{Diagnostic, Subdiagnostic}; +use rustc_macros::{Diagnostic, LintDiagnostic, Subdiagnostic}; use rustc_middle::ty::Ty; use rustc_middle::ty::layout::LayoutError; use rustc_span::{Span, Symbol}; @@ -1114,3 +1114,15 @@ impl Diagnostic<'_, G> for TargetFeatureDisableOrEnable<'_ #[derive(Diagnostic)] #[diag(codegen_ssa_aix_strip_not_used)] pub(crate) struct AixStripNotUsed; + +#[derive(LintDiagnostic)] +#[diag(codegen_ssa_mixed_export_name_and_no_mangle)] +pub(crate) struct MixedExportNameAndNoMangle { + #[label] + pub no_mangle: Span, + pub no_mangle_attr: String, + #[note] + pub export_name: Span, + #[suggestion(style = "verbose", code = "", applicability = "machine-applicable")] + pub removal_span: Span, +} diff --git a/tests/ui/asm/naked-functions.rs b/tests/ui/asm/naked-functions.rs index 5c58f1498cc97..e7e5d84f2a5da 100644 --- a/tests/ui/asm/naked-functions.rs +++ b/tests/ui/asm/naked-functions.rs @@ -219,7 +219,6 @@ pub unsafe extern "C" fn compatible_must_use_attributes() -> u64 { #[export_name = "exported_function_name"] #[link_section = ".custom_section"] -#[no_mangle] #[naked] pub unsafe extern "C" fn compatible_ffi_attributes_1() { naked_asm!("", options(raw)); diff --git a/tests/ui/attributes/mixed_export_name_and_no_mangle.fixed b/tests/ui/attributes/mixed_export_name_and_no_mangle.fixed new file mode 100644 index 0000000000000..7224d4289e3fa --- /dev/null +++ b/tests/ui/attributes/mixed_export_name_and_no_mangle.fixed @@ -0,0 +1,14 @@ +// issue: rust-lang/rust#47446 +//@ run-rustfix +//@ check-pass + +#![warn(unused_attributes)] +//~^ WARN `#[no_mangle]` attribute may not be used in combination with `#[export_name]` [unused_attributes] +#[export_name = "foo"] +pub fn bar() {} + +//~^ WARN `#[unsafe(no_mangle)]` attribute may not be used in combination with `#[export_name]` [unused_attributes] +#[export_name = "baz"] +pub fn bak() {} + +fn main() {} diff --git a/tests/ui/attributes/mixed_export_name_and_no_mangle.rs b/tests/ui/attributes/mixed_export_name_and_no_mangle.rs new file mode 100644 index 0000000000000..149a7904e1ea5 --- /dev/null +++ b/tests/ui/attributes/mixed_export_name_and_no_mangle.rs @@ -0,0 +1,16 @@ +// issue: rust-lang/rust#47446 +//@ run-rustfix +//@ check-pass + +#![warn(unused_attributes)] +#[no_mangle] +//~^ WARN `#[no_mangle]` attribute may not be used in combination with `#[export_name]` [unused_attributes] +#[export_name = "foo"] +pub fn bar() {} + +#[unsafe(no_mangle)] +//~^ WARN `#[unsafe(no_mangle)]` attribute may not be used in combination with `#[export_name]` [unused_attributes] +#[export_name = "baz"] +pub fn bak() {} + +fn main() {} diff --git a/tests/ui/attributes/mixed_export_name_and_no_mangle.stderr b/tests/ui/attributes/mixed_export_name_and_no_mangle.stderr new file mode 100644 index 0000000000000..ba63127ba2db8 --- /dev/null +++ b/tests/ui/attributes/mixed_export_name_and_no_mangle.stderr @@ -0,0 +1,39 @@ +warning: `#[no_mangle]` attribute may not be used in combination with `#[export_name]` + --> $DIR/mixed_export_name_and_no_mangle.rs:6:1 + | +LL | #[no_mangle] + | ^^^^^^^^^^^^ `#[no_mangle]` is ignored + | +note: `#[export_name]` takes precedence + --> $DIR/mixed_export_name_and_no_mangle.rs:8:1 + | +LL | #[export_name = "foo"] + | ^^^^^^^^^^^^^^^^^^^^^^ +note: the lint level is defined here + --> $DIR/mixed_export_name_and_no_mangle.rs:5:9 + | +LL | #![warn(unused_attributes)] + | ^^^^^^^^^^^^^^^^^ +help: remove the `#[no_mangle]` attribute + | +LL - #[no_mangle] + | + +warning: `#[unsafe(no_mangle)]` attribute may not be used in combination with `#[export_name]` + --> $DIR/mixed_export_name_and_no_mangle.rs:11:1 + | +LL | #[unsafe(no_mangle)] + | ^^^^^^^^^^^^^^^^^^^^ `#[unsafe(no_mangle)]` is ignored + | +note: `#[export_name]` takes precedence + --> $DIR/mixed_export_name_and_no_mangle.rs:13:1 + | +LL | #[export_name = "baz"] + | ^^^^^^^^^^^^^^^^^^^^^^ +help: remove the `#[unsafe(no_mangle)]` attribute + | +LL - #[unsafe(no_mangle)] + | + +warning: 2 warnings emitted +