Remove some more #![feature(custom_attribute)]s

src/doc/rustc/src/lints/listing/warn-by-default.md

@@ -728,19 +728,17 @@ This lint detects attributes that were not used by the compiler. Some
 example code that triggers this lint:
 
 ```rust
-#![feature(custom_attribute)]
-
-#![mutable_doc]
+#![macro_export]
 ```
 
 This will produce:
 
 ```text
 warning: unused attribute
- --> src/main.rs:4:1
+ --> src/main.rs:1:1
   |
-4 | #![mutable_doc]
-  | ^^^^^^^^^^^^^^^
+1 | #![macro_export]
+  | ^^^^^^^^^^^^^^^^
   |
 ```
 

src/test/ui/lint/lint-obsolete-attr.rs

@@ -1,12 +1,8 @@
 // When denying at the crate level, be sure to not get random warnings from the
 // injected intrinsics by the compiler.
 
-#![deny(unused_attributes)]
-#![allow(dead_code)]
-#![feature(custom_attribute)]
+#[ab_isize="stdcall"] extern {} //~ ERROR attribute `ab_isize` is currently unknown
 
-#[ab_isize="stdcall"] extern {} //~ ERROR unused attribute
-
-#[fixed_stack_segment] fn f() {} //~ ERROR unused attribute
+#[fixed_stack_segment] fn f() {} //~ ERROR attribute `fixed_stack_segment` is currently unknown
 
 fn main() {}

src/test/ui/lint/lint-obsolete-attr.stderr

@@ -1,20 +1,21 @@
-error: unused attribute
-  --> $DIR/lint-obsolete-attr.rs:8:1
+error[E0658]: The attribute `fixed_stack_segment` is currently unknown to the compiler and may have meaning added to it in the future
+  --> $DIR/lint-obsolete-attr.rs:6:3
    |
-LL | #[ab_isize="stdcall"] extern {}
-   | ^^^^^^^^^^^^^^^^^^^^^
-   |
-note: lint level defined here
-  --> $DIR/lint-obsolete-attr.rs:4:9
+LL | #[fixed_stack_segment] fn f() {}
+   |   ^^^^^^^^^^^^^^^^^^^
    |
-LL | #![deny(unused_attributes)]
-   |         ^^^^^^^^^^^^^^^^^
+   = note: for more information, see https://github.com/rust-lang/rust/issues/29642
+   = help: add #![feature(custom_attribute)] to the crate attributes to enable
 
-error: unused attribute
-  --> $DIR/lint-obsolete-attr.rs:10:1
+error[E0658]: The attribute `ab_isize` is currently unknown to the compiler and may have meaning added to it in the future
+  --> $DIR/lint-obsolete-attr.rs:4:3
    |
-LL | #[fixed_stack_segment] fn f() {}
-   | ^^^^^^^^^^^^^^^^^^^^^^
+LL | #[ab_isize="stdcall"] extern {}
+   |   ^^^^^^^^
+   |
+   = note: for more information, see https://github.com/rust-lang/rust/issues/29642
+   = help: add #![feature(custom_attribute)] to the crate attributes to enable
 
 error: aborting due to 2 previous errors
 
+For more information about this error, try `rustc --explain E0658`.

src/test/ui/lint/lint-unknown-attr.rs

@@ -1,11 +1,10 @@
 // When denying at the crate level, be sure to not get random warnings from the
 // injected intrinsics by the compiler.
 
-#![feature(custom_attribute)]
-#![deny(unused_attributes)]
+#![feature(custom_inner_attributes)]
 
-#![mutable_doc] //~ ERROR unused attribute
+#![mutable_doc] //~ ERROR attribute `mutable_doc` is currently unknown
 
-#[dance] mod a {} //~ ERROR unused attribute
+#[dance] mod a {} //~ ERROR attribute `dance` is currently unknown
 
-#[dance] fn main() {} //~ ERROR unused attribute
+#[dance] fn main() {} //~ ERROR attribute `dance` is currently unknown

src/test/ui/lint/lint-unknown-attr.stderr

@@ -1,26 +1,30 @@
-error: unused attribute
-  --> $DIR/lint-unknown-attr.rs:9:1
+error[E0658]: The attribute `mutable_doc` is currently unknown to the compiler and may have meaning added to it in the future
+  --> $DIR/lint-unknown-attr.rs:6:4
    |
-LL | #[dance] mod a {}
-   | ^^^^^^^^
+LL | #![mutable_doc]
+   |    ^^^^^^^^^^^
    |
-note: lint level defined here
-  --> $DIR/lint-unknown-attr.rs:5:9
+   = note: for more information, see https://github.com/rust-lang/rust/issues/29642
+   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+
+error[E0658]: The attribute `dance` is currently unknown to the compiler and may have meaning added to it in the future
+  --> $DIR/lint-unknown-attr.rs:8:3
    |
-LL | #![deny(unused_attributes)]
-   |         ^^^^^^^^^^^^^^^^^
+LL | #[dance] mod a {}
+   |   ^^^^^
+   |
+   = note: for more information, see https://github.com/rust-lang/rust/issues/29642
+   = help: add #![feature(custom_attribute)] to the crate attributes to enable
 
-error: unused attribute
-  --> $DIR/lint-unknown-attr.rs:11:1
+error[E0658]: The attribute `dance` is currently unknown to the compiler and may have meaning added to it in the future
+  --> $DIR/lint-unknown-attr.rs:10:3
    |
 LL | #[dance] fn main() {}
-   | ^^^^^^^^
-
-error: unused attribute
-  --> $DIR/lint-unknown-attr.rs:7:1
+   |   ^^^^^
    |
-LL | #![mutable_doc]
-   | ^^^^^^^^^^^^^^^
+   = note: for more information, see https://github.com/rust-lang/rust/issues/29642
+   = help: add #![feature(custom_attribute)] to the crate attributes to enable
 
 error: aborting due to 3 previous errors
 
+For more information about this error, try `rustc --explain E0658`.

src/test/ui/proc-macro/resolve-error.rs

@@ -2,8 +2,6 @@
 // aux-build:derive-clona.rs
 // aux-build:test-macros.rs
 
-#![feature(custom_attribute)]
-
 #[macro_use]
 extern crate derive_foo;
 #[macro_use]
@@ -25,10 +23,12 @@ macro_rules! attr_proc_mac {
 //~^ ERROR cannot find
 struct Foo;
 
-#[attr_proc_macra] // OK, interpreted as a custom attribute
+// Interpreted as a feature gated custom attribute
+#[attr_proc_macra] //~ ERROR attribute `attr_proc_macra` is currently unknown
 struct Bar;
 
-#[FooWithLongNan]  // OK, interpreted as a custom attribute
+// Interpreted as a feature gated custom attribute
+#[FooWithLongNan] //~ ERROR attribute `FooWithLongNan` is currently unknown
 struct Asdf;
 
 #[derive(Dlone)]

src/test/ui/proc-macro/resolve-error.stderr

@@ -1,5 +1,23 @@
+error[E0658]: The attribute `attr_proc_macra` is currently unknown to the compiler and may have meaning added to it in the future
+  --> $DIR/resolve-error.rs:27:3
+   |
+LL | #[attr_proc_macra]
+   |   ^^^^^^^^^^^^^^^
+   |
+   = note: for more information, see https://github.com/rust-lang/rust/issues/29642
+   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+
+error[E0658]: The attribute `FooWithLongNan` is currently unknown to the compiler and may have meaning added to it in the future
+  --> $DIR/resolve-error.rs:31:3
+   |
+LL | #[FooWithLongNan]
+   |   ^^^^^^^^^^^^^^
+   |
+   = note: for more information, see https://github.com/rust-lang/rust/issues/29642
+   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+
 error: cannot find derive macro `FooWithLongNan` in this scope
-  --> $DIR/resolve-error.rs:24:10
+  --> $DIR/resolve-error.rs:22:10
    |
 LL | #[derive(FooWithLongNan)]
    |          ^^^^^^^^^^^^^^ help: try: `FooWithLongName`
@@ -46,5 +64,6 @@ error: cannot find macro `bang_proc_macrp!` in this scope
 LL |     bang_proc_macrp!();
    |     ^^^^^^^^^^^^^^^ help: you could try the macro: `bang_proc_macro`
 
-error: aborting due to 8 previous errors
+error: aborting due to 10 previous errors
 
+For more information about this error, try `rustc --explain E0658`.

src/test/ui/tool-attributes/tool-attributes-misplaced-1.rs

@@ -1,12 +1,11 @@
-#![feature(custom_attribute)]
-
 type A = rustfmt; //~ ERROR expected type, found tool module `rustfmt`
 type B = rustfmt::skip; //~ ERROR expected type, found tool attribute `rustfmt::skip`
 
 #[derive(rustfmt)] //~ ERROR cannot find derive macro `rustfmt` in this scope
 struct S;
 
-#[rustfmt] // OK, interpreted as a custom attribute
+// Interpreted as a feature gated custom attribute
+#[rustfmt] //~ ERROR attribute `rustfmt` is currently unknown
 fn check() {}
 
 #[rustfmt::skip] // OK

src/test/ui/tool-attributes/tool-attributes-misplaced-1.stderr

@@ -1,39 +1,49 @@
+error[E0658]: The attribute `rustfmt` is currently unknown to the compiler and may have meaning added to it in the future
+  --> $DIR/tool-attributes-misplaced-1.rs:8:3
+   |
+LL | #[rustfmt]
+   |   ^^^^^^^
+   |
+   = note: for more information, see https://github.com/rust-lang/rust/issues/29642
+   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+
 error: cannot find derive macro `rustfmt` in this scope
-  --> $DIR/tool-attributes-misplaced-1.rs:6:10
+  --> $DIR/tool-attributes-misplaced-1.rs:4:10
    |
 LL | #[derive(rustfmt)]
    |          ^^^^^^^
 
 error: cannot find macro `rustfmt!` in this scope
-  --> $DIR/tool-attributes-misplaced-1.rs:15:5
+  --> $DIR/tool-attributes-misplaced-1.rs:14:5
    |
 LL |     rustfmt!();
    |     ^^^^^^^
 
 error[E0573]: expected type, found tool module `rustfmt`
-  --> $DIR/tool-attributes-misplaced-1.rs:3:10
+  --> $DIR/tool-attributes-misplaced-1.rs:1:10
    |
 LL | type A = rustfmt;
    |          ^^^^^^^ not a type
 
 error[E0573]: expected type, found tool attribute `rustfmt::skip`
-  --> $DIR/tool-attributes-misplaced-1.rs:4:10
+  --> $DIR/tool-attributes-misplaced-1.rs:2:10
    |
 LL | type B = rustfmt::skip;
    |          ^^^^^^^^^^^^^ not a type
 
 error[E0423]: expected value, found tool module `rustfmt`
-  --> $DIR/tool-attributes-misplaced-1.rs:14:5
+  --> $DIR/tool-attributes-misplaced-1.rs:13:5
    |
 LL |     rustfmt;
    |     ^^^^^^^ not a value
 
 error[E0423]: expected value, found tool attribute `rustfmt::skip`
-  --> $DIR/tool-attributes-misplaced-1.rs:17:5
+  --> $DIR/tool-attributes-misplaced-1.rs:16:5
    |
 LL |     rustfmt::skip;
    |     ^^^^^^^^^^^^^ not a value
 
-error: aborting due to 6 previous errors
+error: aborting due to 7 previous errors
 
-For more information about this error, try `rustc --explain E0423`.
+Some errors have detailed explanations: E0423, E0658.
+For more information about an error, try `rustc --explain E0423`.