Error on invalid placements for unstable attributes

compiler/rustc_attr_parsing/src/attributes/allow_unstable.rs

@@ -12,12 +12,8 @@ impl CombineAttributeParser for AllowInternalUnstableParser {
     type Item = (Symbol, Span);
     const CONVERT: ConvertFn<Self::Item> =
         |items, span| AttributeKind::AllowInternalUnstable(items, span);
-    const ALLOWED_TARGETS: AllowedTargets<'_> = AllowedTargets::AllowList(&[
-        Allow(Target::MacroDef),
-        Allow(Target::Fn),
-        Warn(Target::Field),
-        Warn(Target::Arm),
-    ]);
+    const ALLOWED_TARGETS: AllowedTargets<'_> =
+        AllowedTargets::AllowList(&[Allow(Target::MacroDef), Allow(Target::Fn)]);
     const TEMPLATE: AttributeTemplate = template!(Word, List: &["feat1, feat2, ..."]);
     const STABILITY: AttributeStability = unstable!(allow_internal_unstable);
 

compiler/rustc_attr_parsing/src/attributes/macro_attrs.rs

@@ -131,12 +131,8 @@ pub(crate) struct AllowInternalUnsafeParser;
 impl NoArgsAttributeParser for AllowInternalUnsafeParser {
     const PATH: &[Symbol] = &[sym::allow_internal_unsafe];
     const ON_DUPLICATE: OnDuplicate = OnDuplicate::Ignore;
-    const ALLOWED_TARGETS: AllowedTargets<'_> = AllowedTargets::AllowList(&[
-        Allow(Target::Fn),
-        Allow(Target::MacroDef),
-        Warn(Target::Field),
-        Warn(Target::Arm),
-    ]);
+    const ALLOWED_TARGETS: AllowedTargets<'_> =
+        AllowedTargets::AllowList(&[Allow(Target::Fn), Allow(Target::MacroDef)]);
     const STABILITY: AttributeStability = unstable!(allow_internal_unsafe);
     const CREATE: fn(Span) -> AttributeKind = |span| AttributeKind::AllowInternalUnsafe(span);
 

compiler/rustc_attr_parsing/src/attributes/traits.rs

@@ -8,7 +8,7 @@ use crate::attributes::{NoArgsAttributeParser, SingleAttributeParser};
 use crate::context::AcceptContext;
 use crate::parser::ArgParser;
 use crate::target_checking::AllowedTargets;
-use crate::target_checking::Policy::{Allow, Warn};
+use crate::target_checking::Policy::Allow;
 
 pub(crate) struct RustcSkipDuringMethodDispatchParser;
 impl SingleAttributeParser for RustcSkipDuringMethodDispatchParser {
@@ -63,12 +63,7 @@ impl NoArgsAttributeParser for RustcParenSugarParser {
 pub(crate) struct MarkerParser;
 impl NoArgsAttributeParser for MarkerParser {
     const PATH: &[Symbol] = &[sym::marker];
-    const ALLOWED_TARGETS: AllowedTargets<'_> = AllowedTargets::AllowList(&[
-        Allow(Target::Trait),
-        Warn(Target::Field),
-        Warn(Target::Arm),
-        Warn(Target::MacroDef),
-    ]);
+    const ALLOWED_TARGETS: AllowedTargets<'_> = AllowedTargets::AllowList(&[Allow(Target::Trait)]);
     const STABILITY: AttributeStability = unstable!(marker_trait_attr);
     const CREATE: fn(Span) -> AttributeKind = |_| AttributeKind::Marker;
 }

tests/ui/internal/internal-unstable.rs

@@ -8,8 +8,7 @@ extern crate internal_unstable;
 
 struct Baz {
     #[allow_internal_unstable] //~ ERROR `allow_internal_unstable` expects a list of feature names
-    //~^ WARN cannot be used on
-    //~| WARN previously accepted
+    //~^ ERROR cannot be used on
     baz: u8,
 }
 
@@ -59,8 +58,7 @@ fn main() {
 
     match true {
         #[allow_internal_unstable] //~ ERROR `allow_internal_unstable` expects a list of feature names
-        //~^ WARN cannot be used on
-        //~| WARN previously accepted
+        //~^ ERROR cannot be used on
         _ => {}
     }
 

tests/ui/internal/internal-unstable.stderr

@@ -4,14 +4,30 @@ error: `allow_internal_unstable` expects a list of feature names
 LL |     #[allow_internal_unstable]
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
 
+error: the `allow_internal_unstable` attribute cannot be used on struct fields
+  --> $DIR/internal-unstable.rs:10:7
+   |
+LL |     #[allow_internal_unstable]
+   |       ^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = help: the `allow_internal_unstable` attribute can be applied to functions and macro defs
+
 error: `allow_internal_unstable` expects a list of feature names
-  --> $DIR/internal-unstable.rs:61:9
+  --> $DIR/internal-unstable.rs:60:9
    |
 LL |         #[allow_internal_unstable]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^
 
+error: the `allow_internal_unstable` attribute cannot be used on match arms
+  --> $DIR/internal-unstable.rs:60:11
+   |
+LL |         #[allow_internal_unstable]
+   |           ^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = help: the `allow_internal_unstable` attribute can be applied to functions and macro defs
+
 error[E0658]: use of unstable library feature `function`
-  --> $DIR/internal-unstable.rs:50:25
+  --> $DIR/internal-unstable.rs:49:25
    |
 LL |     pass_through_allow!(internal_unstable::unstable());
    |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -20,7 +36,7 @@ LL |     pass_through_allow!(internal_unstable::unstable());
    = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
 
 error[E0658]: use of unstable library feature `function`
-  --> $DIR/internal-unstable.rs:52:27
+  --> $DIR/internal-unstable.rs:51:27
    |
 LL |     pass_through_noallow!(internal_unstable::unstable());
    |                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -29,7 +45,7 @@ LL |     pass_through_noallow!(internal_unstable::unstable());
    = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
 
 error[E0658]: use of unstable library feature `function`
-  --> $DIR/internal-unstable.rs:56:22
+  --> $DIR/internal-unstable.rs:55:22
    |
 LL |     println!("{:?}", internal_unstable::unstable());
    |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -38,7 +54,7 @@ LL |     println!("{:?}", internal_unstable::unstable());
    = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
 
 error[E0658]: use of unstable library feature `function`
-  --> $DIR/internal-unstable.rs:58:10
+  --> $DIR/internal-unstable.rs:57:10
    |
 LL |     bar!(internal_unstable::unstable());
    |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -47,7 +63,7 @@ LL |     bar!(internal_unstable::unstable());
    = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
 
 error[E0658]: use of unstable library feature `function`
-  --> $DIR/internal-unstable.rs:20:9
+  --> $DIR/internal-unstable.rs:19:9
    |
 LL |         internal_unstable::unstable();
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -59,25 +75,6 @@ LL |     bar!(internal_unstable::unstable());
    = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
    = note: this error originates in the macro `foo` which comes from the expansion of the macro `bar` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-warning: the `allow_internal_unstable` attribute cannot be used on struct fields
-  --> $DIR/internal-unstable.rs:10:7
-   |
-LL |     #[allow_internal_unstable]
-   |       ^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = help: the `allow_internal_unstable` attribute can be applied to functions and macro defs
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: requested on the command line with `-W unused-attributes`
-
-warning: the `allow_internal_unstable` attribute cannot be used on match arms
-  --> $DIR/internal-unstable.rs:61:11
-   |
-LL |         #[allow_internal_unstable]
-   |           ^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = help: the `allow_internal_unstable` attribute can be applied to functions and macro defs
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-
-error: aborting due to 7 previous errors; 2 warnings emitted
+error: aborting due to 9 previous errors
 
 For more information about this error, try `rustc --explain E0658`.