Revert "Port #[allow_internal_unsafe] to the new attribute system"

This reverts commit 4f7a6ace9e.

compiler/rustc_attr_parsing/src/attributes/macro_attrs.rs

@@ -113,11 +113,3 @@ impl<S: Stage> AttributeParser<S> for MacroUseParser {
         Some(AttributeKind::MacroUse { span: self.first_span?, arguments: self.state })
     }
 }
-
-pub(crate) struct AllowInternalUnsafeParser;
-
-impl<S: Stage> NoArgsAttributeParser<S> for AllowInternalUnsafeParser {
-    const PATH: &[Symbol] = &[sym::allow_internal_unsafe];
-    const ON_DUPLICATE: OnDuplicate<S> = OnDuplicate::Ignore;
-    const CREATE: fn(Span) -> AttributeKind = |span| AttributeKind::AllowInternalUnsafe(span);
-}

compiler/rustc_attr_parsing/src/context.rs

@@ -33,9 +33,7 @@ use crate::attributes::lint_helpers::{
     AsPtrParser, AutomaticallyDerivedParser, PassByValueParser, PubTransparentParser,
 };
 use crate::attributes::loop_match::{ConstContinueParser, LoopMatchParser};
-use crate::attributes::macro_attrs::{
-    AllowInternalUnsafeParser, MacroEscapeParser, MacroUseParser,
-};
+use crate::attributes::macro_attrs::{MacroEscapeParser, MacroUseParser};
 use crate::attributes::must_use::MustUseParser;
 use crate::attributes::no_implicit_prelude::NoImplicitPreludeParser;
 use crate::attributes::non_exhaustive::NonExhaustiveParser;
@@ -180,7 +178,6 @@ attribute_parsers!(
         Single<SkipDuringMethodDispatchParser>,
         Single<TransparencyParser>,
         Single<WithoutArgs<AllowIncoherentImplParser>>,
-        Single<WithoutArgs<AllowInternalUnsafeParser>>,
         Single<WithoutArgs<AsPtrParser>>,
         Single<WithoutArgs<AutomaticallyDerivedParser>>,
         Single<WithoutArgs<CoherenceIsCoreParser>>,

compiler/rustc_expand/src/base.rs

@@ -905,7 +905,10 @@ impl SyntaxExtension {
             find_attr!(attrs, AttributeKind::AllowInternalUnstable(i, _) => i)
                 .map(|i| i.as_slice())
                 .unwrap_or_default();
-        let allow_internal_unsafe = find_attr!(attrs, AttributeKind::AllowInternalUnsafe(_));
+        // FIXME(jdonszelman): allow_internal_unsafe isn't yet new-style
+        // let allow_internal_unsafe = find_attr!(attrs, AttributeKind::AllowInternalUnsafe);
+        let allow_internal_unsafe =
+            ast::attr::find_by_name(attrs, sym::allow_internal_unsafe).is_some();
 
         let local_inner_macros = ast::attr::find_by_name(attrs, sym::macro_export)
             .and_then(|macro_export| macro_export.meta_item_list())

compiler/rustc_hir/src/attrs/data_structures.rs

@@ -249,9 +249,6 @@ pub enum AttributeKind {
     /// Represents `#[rustc_allow_incoherent_impl]`.
     AllowIncoherentImpl(Span),
 
-    /// Represents `#[allow_internal_unsafe]`.
-    AllowInternalUnsafe(Span),
-
     /// Represents `#[allow_internal_unstable]`.
     AllowInternalUnstable(ThinVec<(Symbol, Span)>, Span),
 

compiler/rustc_hir/src/attrs/encode_cross_crate.rs

@@ -16,7 +16,6 @@ impl AttributeKind {
             Align { .. } => No,
             AllowConstFnUnstable(..) => No,
             AllowIncoherentImpl(..) => No,
-            AllowInternalUnsafe(..) => Yes,
             AllowInternalUnstable(..) => Yes,
             AsPtr(..) => Yes,
             AutomaticallyDerived(..) => Yes,

compiler/rustc_lint/src/builtin.rs

@@ -14,7 +14,6 @@
 //! [`crate::late_lint_methods!`] invocation in `lib.rs`.
 
 use std::fmt::Write;
-use std::slice;
 
 use ast::token::TokenKind;
 use rustc_abi::BackendRepr;
@@ -22,7 +21,6 @@ use rustc_ast::tokenstream::{TokenStream, TokenTree};
 use rustc_ast::visit::{FnCtxt, FnKind};
 use rustc_ast::{self as ast, *};
 use rustc_ast_pretty::pprust::expr_to_string;
-use rustc_attr_parsing::AttributeParser;
 use rustc_errors::{Applicability, LintDiagnostic};
 use rustc_feature::GateIssue;
 use rustc_hir as hir;
@@ -251,16 +249,7 @@ impl UnsafeCode {
 
 impl EarlyLintPass for UnsafeCode {
     fn check_attribute(&mut self, cx: &EarlyContext<'_>, attr: &ast::Attribute) {
-        if AttributeParser::parse_limited(
-            cx.builder.sess(),
-            slice::from_ref(attr),
-            sym::allow_internal_unsafe,
-            attr.span,
-            DUMMY_NODE_ID,
-            Some(cx.builder.features()),
-        )
-        .is_some()
-        {
+        if attr.has_name(sym::allow_internal_unsafe) {
             self.report_unsafe(cx, attr.span, BuiltinUnsafe::AllowInternalUnsafe);
         }
     }

compiler/rustc_passes/messages.ftl

@@ -29,7 +29,7 @@ passes_allow_incoherent_impl =
     `rustc_allow_incoherent_impl` attribute should be applied to impl items
     .label = the only currently supported targets are inherent methods
 
-passes_macro_only_attribute =
+passes_allow_internal_unstable =
     attribute should be applied to a macro
     .label = not a macro
 

compiler/rustc_passes/src/check_attr.rs

@@ -207,9 +207,6 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
                 Attribute::Parsed(AttributeKind::ConstContinue(attr_span)) => {
                     self.check_const_continue(hir_id, *attr_span, target)
                 }
-                Attribute::Parsed(AttributeKind::AllowInternalUnsafe(attr_span)) => {
-                    self.check_allow_internal_unsafe(hir_id, *attr_span, span, target, attrs)
-                }
                 Attribute::Parsed(AttributeKind::AllowInternalUnstable(_, first_span)) => {
                     self.check_allow_internal_unstable(hir_id, *first_span, span, target, attrs)
                 }
@@ -416,6 +413,7 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
                             // internal
                             | sym::prelude_import
                             | sym::panic_handler
+                            | sym::allow_internal_unsafe
                             | sym::lang
                             | sym::needs_allocator
                             | sym::default_lib_allocator
@@ -2214,6 +2212,7 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
 
     /// Outputs an error for `#[allow_internal_unstable]` which can only be applied to macros.
     /// (Allows proc_macro functions)
+    // FIXME(jdonszelmann): if possible, move to attr parsing
     fn check_allow_internal_unstable(
         &self,
         hir_id: HirId,
@@ -2221,42 +2220,6 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
         span: Span,
         target: Target,
         attrs: &[Attribute],
-    ) {
-        self.check_macro_only_attr(
-            hir_id,
-            attr_span,
-            span,
-            target,
-            attrs,
-            "allow_internal_unstable",
-        )
-    }
-
-    /// Outputs an error for `#[allow_internal_unsafe]` which can only be applied to macros.
-    /// (Allows proc_macro functions)
-    fn check_allow_internal_unsafe(
-        &self,
-        hir_id: HirId,
-        attr_span: Span,
-        span: Span,
-        target: Target,
-        attrs: &[Attribute],
-    ) {
-        self.check_macro_only_attr(hir_id, attr_span, span, target, attrs, "allow_internal_unsafe")
-    }
-
-    /// Outputs an error for attributes that can only be applied to macros, such as
-    /// `#[allow_internal_unsafe]` and `#[allow_internal_unstable]`.
-    /// (Allows proc_macro functions)
-    // FIXME(jdonszelmann): if possible, move to attr parsing
-    fn check_macro_only_attr(
-        &self,
-        hir_id: HirId,
-        attr_span: Span,
-        span: Span,
-        target: Target,
-        attrs: &[Attribute],
-        attr_name: &str,
     ) {
         match target {
             Target::Fn => {
@@ -2275,14 +2238,18 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
             // erroneously allowed it and some crates used it accidentally, to be compatible
             // with crates depending on them, we can't throw an error here.
             Target::Field | Target::Arm => {
-                self.inline_attr_str_error_without_macro_def(hir_id, attr_span, attr_name);
+                self.inline_attr_str_error_without_macro_def(
+                    hir_id,
+                    attr_span,
+                    "allow_internal_unstable",
+                );
                 return;
             }
             // otherwise continue out of the match
             _ => {}
         }
 
-        self.tcx.dcx().emit_err(errors::MacroOnlyAttribute { attr_span, span });
+        self.tcx.dcx().emit_err(errors::AllowInternalUnstable { attr_span, span });
     }
 
     /// Checks if the items on the `#[debugger_visualizer]` attribute are valid.

compiler/rustc_passes/src/errors.rs

@@ -643,8 +643,8 @@ pub(crate) struct UsedStatic {
 }
 
 #[derive(Diagnostic)]
-#[diag(passes_macro_only_attribute)]
-pub(crate) struct MacroOnlyAttribute {
+#[diag(passes_allow_internal_unstable)]
+pub(crate) struct AllowInternalUnstable {
     #[primary_span]
     pub attr_span: Span,
     #[label]

tests/ui/attributes/malformed-attrs.stderr

@@ -145,6 +145,12 @@ LL - #[macro_export = 18]
 LL + #[macro_export]
    |
 
+error: malformed `allow_internal_unsafe` attribute input
+  --> $DIR/malformed-attrs.rs:213:1
+   |
+LL | #[allow_internal_unsafe = 1]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: must be of the form: `#[allow_internal_unsafe]`
+
 error: the `#[proc_macro]` attribute is only usable with crates of the `proc-macro` crate type
   --> $DIR/malformed-attrs.rs:96:1
    |
@@ -555,15 +561,6 @@ error: valid forms for the attribute are `#[macro_use(name1, name2, ...)]` and `
 LL | #[macro_use = 1]
    | ^^^^^^^^^^^^^^^^
 
-error[E0565]: malformed `allow_internal_unsafe` attribute input
-  --> $DIR/malformed-attrs.rs:213:1
-   |
-LL | #[allow_internal_unsafe = 1]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^---^
-   | |                       |
-   | |                       didn't expect any arguments here
-   | help: must be of the form: `#[allow_internal_unsafe]`
-
 error[E0565]: malformed `type_const` attribute input
   --> $DIR/malformed-attrs.rs:140:5
    |