Rollup merge of #142964 - GrigorenkoPV:attributes/argless, r=oli-obk

Attribute rework: a parser for single attributes without arguments

Part of rust-lang/rust#131229

r? `@jdonszelmann`

I think code (with comments) speaks for itself.

The only subtlety: now `#[cold]`, `#[no_mangle]`, & `#[track_caller]` do not get thrown away when malformed (i.e. have arguments). This doesn't matter too much (I think), because an error gets emitted either way, so the compilation will not finish.

compiler/rustc_attr_parsing/src/context.rs

@@ -37,7 +37,7 @@ use crate::attributes::stability::{
 };
 use crate::attributes::traits::SkipDuringMethodDispatchParser;
 use crate::attributes::transparency::TransparencyParser;
-use crate::attributes::{AttributeParser as _, Combine, Single};
+use crate::attributes::{AttributeParser as _, Combine, Single, WithoutArgs};
 use crate::parser::{ArgParser, MetaItemParser, PathParser};
 use crate::session_diagnostics::{AttributeParseError, AttributeParseErrorReason, UnknownMetaItem};
 
@@ -58,6 +58,7 @@ macro_rules! attribute_parsers {
             use super::*;
             type Combine<T> = super::Combine<T, Early>;
             type Single<T> = super::Single<T, Early>;
+            type WithoutArgs<T> = super::WithoutArgs<T, Early>;
 
             attribute_parsers!(@[Early] pub(crate) static $name = [$($names),*];);
         }
@@ -65,6 +66,7 @@ macro_rules! attribute_parsers {
             use super::*;
             type Combine<T> = super::Combine<T, Late>;
             type Single<T> = super::Single<T, Late>;
+            type WithoutArgs<T> = super::WithoutArgs<T, Late>;
 
             attribute_parsers!(@[Late] pub(crate) static $name = [$($names),*];);
         }
@@ -119,28 +121,28 @@ attribute_parsers!(
         // tidy-alphabetical-end
 
         // tidy-alphabetical-start
-        Single<AsPtrParser>,
-        Single<ColdParser>,
-        Single<ConstContinueParser>,
-        Single<ConstStabilityIndirectParser>,
         Single<DeprecationParser>,
         Single<ExportNameParser>,
         Single<InlineParser>,
         Single<LinkNameParser>,
         Single<LinkSectionParser>,
-        Single<LoopMatchParser>,
-        Single<MayDangleParser>,
         Single<MustUseParser>,
-        Single<NoMangleParser>,
         Single<OptimizeParser>,
-        Single<PubTransparentParser>,
         Single<RustcForceInlineParser>,
         Single<RustcLayoutScalarValidRangeEnd>,
         Single<RustcLayoutScalarValidRangeStart>,
         Single<RustcObjectLifetimeDefaultParser>,
         Single<SkipDuringMethodDispatchParser>,
-        Single<TrackCallerParser>,
         Single<TransparencyParser>,
+        Single<WithoutArgs<AsPtrParser>>,
+        Single<WithoutArgs<ColdParser>>,
+        Single<WithoutArgs<ConstContinueParser>>,
+        Single<WithoutArgs<ConstStabilityIndirectParser>>,
+        Single<WithoutArgs<LoopMatchParser>>,
+        Single<WithoutArgs<MayDangleParser>>,
+        Single<WithoutArgs<NoMangleParser>>,
+        Single<WithoutArgs<PubTransparentParser>>,
+        Single<WithoutArgs<TrackCallerParser>>,
         // tidy-alphabetical-end
     ];
 );