normalize use of backticks in compiler messages for libsyntax/feature_gate

https://github.com/rust-lang/rust/issues/60532

src/libsyntax/feature_gate.rs

@@ -1465,7 +1465,7 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
         cfg_fn!(dropck_eyepatch))),
     (sym::unwind, Whitelisted, template!(List: "allowed|aborts"), Gated(Stability::Unstable,
                                 sym::unwind_attributes,
-                                "#[unwind] is experimental",
+                                "`#[unwind]` is experimental",
                                 cfg_fn!(unwind_attributes))),
     (sym::used, Whitelisted, template!(Word), Ungated),
 
@@ -1551,13 +1551,13 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
 
     (sym::alloc_error_handler, Normal, template!(Word), Gated(Stability::Unstable,
                         sym::alloc_error_handler,
-                        "#[alloc_error_handler] is an unstable feature",
+                        "`#[alloc_error_handler]` is an unstable feature",
                         cfg_fn!(alloc_error_handler))),
 
     // RFC 2412
     (sym::optimize, Whitelisted, template!(List: "size|speed"), Gated(Stability::Unstable,
                             sym::optimize_attribute,
-                            "#[optimize] attribute is an unstable feature",
+                            "`#[optimize]` attribute is an unstable feature",
                             cfg_fn!(optimize_attribute))),
 
     // Crate level attributes
@@ -1674,7 +1674,7 @@ impl<'a> Context<'a> {
                 if let Some(content) = attr.meta_item_list() {
                     if content.iter().any(|c| c.check_name(sym::include)) {
                         gate_feature!(self, external_doc, attr.span,
-                            "#[doc(include = \"...\")] is experimental"
+                            "`#[doc(include = \"...\")]` is experimental"
                         );
                     }
                 }
@@ -1803,7 +1803,7 @@ fn leveled_feature_err<'a, S: Into<MultiSpan>>(
 
     // #23973: do not suggest `#![feature(...)]` if we are in beta/stable
     if sess.unstable_features.is_nightly_build() {
-        err.help(&format!("add #![feature({})] to the crate attributes to enable", feature));
+        err.help(&format!("add `#![feature({})]` to the crate attributes to enable", feature));
     }
 
     // If we're on stable and only emitting a "soft" warning, add a note to
@@ -1985,23 +1985,23 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
             if let Some(content) = attr.meta_item_list() {
                 if content.len() == 1 && content[0].check_name(sym::cfg) {
                     gate_feature_post!(&self, doc_cfg, attr.span,
-                        "#[doc(cfg(...))] is experimental"
+                        "`#[doc(cfg(...))]` is experimental"
                     );
                 } else if content.iter().any(|c| c.check_name(sym::masked)) {
                     gate_feature_post!(&self, doc_masked, attr.span,
-                        "#[doc(masked)] is experimental"
+                        "`#[doc(masked)]` is experimental"
                     );
                 } else if content.iter().any(|c| c.check_name(sym::spotlight)) {
                     gate_feature_post!(&self, doc_spotlight, attr.span,
-                        "#[doc(spotlight)] is experimental"
+                        "`#[doc(spotlight)]` is experimental"
                     );
                 } else if content.iter().any(|c| c.check_name(sym::alias)) {
                     gate_feature_post!(&self, doc_alias, attr.span,
-                        "#[doc(alias = \"...\")] is experimental"
+                        "`#[doc(alias = \"...\")]` is experimental"
                     );
                 } else if content.iter().any(|c| c.check_name(sym::keyword)) {
                     gate_feature_post!(&self, doc_keyword, attr.span,
-                        "#[doc(keyword = \"...\")] is experimental"
+                        "`#[doc(keyword = \"...\")]` is experimental"
                     );
                 }
             }
@@ -2044,13 +2044,13 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
                 }
                 if attr::contains_name(&i.attrs[..], sym::start) {
                     gate_feature_post!(&self, start, i.span,
-                                      "a #[start] function is an experimental \
+                                      "a `#[start]` function is an experimental \
                                        feature whose signature may change \
                                        over time");
                 }
                 if attr::contains_name(&i.attrs[..], sym::main) {
                     gate_feature_post!(&self, main, i.span,
-                                       "declaration of a nonstandard #[main] \
+                                       "declaration of a non-standard `#[main]` \
                                         function may change over time, for now \
                                         a top-level `fn main()` is required");
                 }
@@ -2638,7 +2638,7 @@ fn maybe_stage_features(span_handler: &Handler, krate: &ast::Crate,
             if attr.check_name(sym::feature) {
                 let release_channel = option_env!("CFG_RELEASE_CHANNEL").unwrap_or("(unknown)");
                 span_err!(span_handler, attr.span, E0554,
-                          "#![feature] may not be used on the {} release channel",
+                          "`#![feature]` may not be used on the {} release channel",
                           release_channel);
             }
         }

src/test/ui-fulldeps/gated-plugin.stderr

@@ -5,7 +5,7 @@ LL | #![plugin(attr_plugin_test)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29597
-   = help: add #![feature(plugin)] to the crate attributes to enable
+   = help: add `#![feature(plugin)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui-fulldeps/hash-stable-is-unstable.stderr

@@ -9,7 +9,7 @@ LL | extern crate rustc_data_structures;
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/27812
-   = help: add #![feature(rustc_private)] to the crate attributes to enable
+   = help: add `#![feature(rustc_private)]` to the crate attributes to enable
 
 error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead?
   --> $DIR/hash-stable-is-unstable.rs:5:1
@@ -18,7 +18,7 @@ LL | extern crate rustc;
    | ^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/27812
-   = help: add #![feature(rustc_private)] to the crate attributes to enable
+   = help: add `#![feature(rustc_private)]` to the crate attributes to enable
 
 error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead?
   --> $DIR/hash-stable-is-unstable.rs:7:1
@@ -27,7 +27,7 @@ LL | extern crate rustc_macros;
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/27812
-   = help: add #![feature(rustc_private)] to the crate attributes to enable
+   = help: add `#![feature(rustc_private)]` to the crate attributes to enable
 
 error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead?
   --> $DIR/hash-stable-is-unstable.rs:10:5
@@ -36,7 +36,7 @@ LL | use rustc_macros::HashStable;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/27812
-   = help: add #![feature(rustc_private)] to the crate attributes to enable
+   = help: add `#![feature(rustc_private)]` to the crate attributes to enable
 
 error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead?
   --> $DIR/hash-stable-is-unstable.rs:13:10
@@ -45,7 +45,7 @@ LL | #[derive(HashStable)]
    |          ^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/27812
-   = help: add #![feature(rustc_private)] to the crate attributes to enable
+   = help: add `#![feature(rustc_private)]` to the crate attributes to enable
 
 error: aborting due to 6 previous errors
 

src/test/ui/async-await/feature-async-closure.stderr

@@ -5,7 +5,7 @@ LL |     let _ = async || {};
    |             ^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/62290
-   = help: add #![feature(async_closure)] to the crate attributes to enable
+   = help: add `#![feature(async_closure)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

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

@@ -5,7 +5,7 @@ LL | #[fixed_stack_segment] fn f() {}
    |   ^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `ab_isize` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/obsolete-attr.rs:3:3
@@ -14,7 +14,7 @@ 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
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error: aborting due to 2 previous errors
 

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

@@ -5,7 +5,7 @@ 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
+   = 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/unknown-attr.rs:7:3
@@ -14,7 +14,7 @@ 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
+   = 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/unknown-attr.rs:9:3
@@ -23,7 +23,7 @@ LL | #[dance] fn main() {}
    |   ^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error: aborting due to 3 previous errors
 

src/test/ui/cast/cast-ptr-to-int-const.stderr

@@ -5,7 +5,7 @@ LL |         main as u32
    |         ^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51910
-   = help: add #![feature(const_raw_ptr_to_usize_cast)] to the crate attributes to enable
+   = help: add `#![feature(const_raw_ptr_to_usize_cast)]` to the crate attributes to enable
 
 error[E0658]: casting pointers to integers in constants is unstable
   --> $DIR/cast-ptr-to-int-const.rs:9:9
@@ -14,7 +14,7 @@ LL |         &Y as *const u32 as u32
    |         ^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51910
-   = help: add #![feature(const_raw_ptr_to_usize_cast)] to the crate attributes to enable
+   = help: add `#![feature(const_raw_ptr_to_usize_cast)]` to the crate attributes to enable
 
 error: aborting due to 2 previous errors
 

src/test/ui/conditional-compilation/cfg-attr-crate-2.stderr

@@ -5,7 +5,7 @@ LL | #![cfg_attr(broken, no_core)]
    |                     ^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29639
-   = help: add #![feature(no_core)] to the crate attributes to enable
+   = help: add `#![feature(no_core)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/conditional-compilation/cfg-attr-multi-invalid-1.stderr

@@ -5,7 +5,7 @@ LL | #![cfg_attr(broken, no_core, no_std)]
    |                     ^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29639
-   = help: add #![feature(no_core)] to the crate attributes to enable
+   = help: add `#![feature(no_core)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/conditional-compilation/cfg-attr-multi-invalid-2.stderr

@@ -5,7 +5,7 @@ LL | #![cfg_attr(broken, no_std, no_core)]
    |                             ^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29639
-   = help: add #![feature(no_core)] to the crate attributes to enable
+   = help: add `#![feature(no_core)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/conditional-compilation/cfg-attr-unknown-attribute-macro-expansion.stderr

@@ -8,7 +8,7 @@ LL | foo!();
    | ------- in this macro invocation
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/conditional-compilation/cfg-generic-params.stderr

@@ -23,7 +23,7 @@ LL | fn f_lt_yes<#[cfg_attr(yes, unknown)] '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
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `unknown` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/cfg-generic-params.rs:21:29
@@ -32,7 +32,7 @@ LL | fn f_ty_yes<#[cfg_attr(yes, unknown)] T>() {}
    |                             ^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `unknown` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/cfg-generic-params.rs:24:34
@@ -41,7 +41,7 @@ LL | type FnYes = for<#[cfg_attr(yes, unknown)] 'a> fn();
    |                                  ^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `unknown` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/cfg-generic-params.rs:28:40
@@ -50,7 +50,7 @@ LL | type PolyYes = dyn for<#[cfg_attr(yes, unknown)] 'a> Copy;
    |                                        ^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `unknown` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/cfg-generic-params.rs:32:43
@@ -59,7 +59,7 @@ LL | struct WhereYes where for<#[cfg_attr(yes, unknown)] 'a> u8: Copy;
    |                                           ^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error: aborting due to 8 previous errors
 

src/test/ui/const-generics/const-param-in-trait-ungated.stderr

@@ -5,7 +5,7 @@ LL | trait Trait<const T: ()> {}
    |                   ^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44580
-   = help: add #![feature(const_generics)] to the crate attributes to enable
+   = help: add `#![feature(const_generics)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/const-generics/const-param-type-depends-on-type-param-ungated.stderr

@@ -11,7 +11,7 @@ LL | struct B<T, const N: T>(PhantomData<[T; N]>);
    |                   ^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44580
-   = help: add #![feature(const_generics)] to the crate attributes to enable
+   = help: add `#![feature(const_generics)]` to the crate attributes to enable
 
 error: aborting due to 2 previous errors
 

src/test/ui/const-generics/issue-60263.stderr

@@ -5,7 +5,7 @@ LL | struct B<const I: u8>;
    |                ^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44580
-   = help: add #![feature(const_generics)] to the crate attributes to enable
+   = help: add `#![feature(const_generics)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/consts/const-deref-ptr.stderr

@@ -5,7 +5,7 @@ LL |     static C: u64 = unsafe {*(0xdeadbeef as *const u64)};
    |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51911
-   = help: add #![feature(const_raw_ptr_deref)] to the crate attributes to enable
+   = help: add `#![feature(const_raw_ptr_deref)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/consts/const-eval/feature-gate-const_fn_union.stderr

@@ -5,7 +5,7 @@ LL |     Foo { u }.i
    |     ^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51909
-   = help: add #![feature(const_fn_union)] to the crate attributes to enable
+   = help: add `#![feature(const_fn_union)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/consts/const-eval/feature-gate-const_panic.stderr

@@ -5,7 +5,7 @@ LL | const Z: () = panic!("cheese");
    |               ^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51999
-   = help: add #![feature(const_panic)] to the crate attributes to enable
+   = help: add `#![feature(const_panic)]` to the crate attributes to enable
    = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)
 
 error[E0658]: panicking in constants is unstable
@@ -15,7 +15,7 @@ LL | const X: () = unimplemented!();
    |               ^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51999
-   = help: add #![feature(const_panic)] to the crate attributes to enable
+   = help: add `#![feature(const_panic)]` to the crate attributes to enable
    = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)
 
 error[E0658]: panicking in constants is unstable
@@ -25,7 +25,7 @@ LL | const Y: () = unreachable!();
    |               ^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51999
-   = help: add #![feature(const_panic)] to the crate attributes to enable
+   = help: add `#![feature(const_panic)]` to the crate attributes to enable
    = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)
 
 error: aborting due to 3 previous errors

src/test/ui/consts/const-eval/match-test-ptr-null.stderr

@@ -5,7 +5,7 @@ LL |         match &1 as *const i32 as usize {
    |               ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51910
-   = help: add #![feature(const_raw_ptr_to_usize_cast)] to the crate attributes to enable
+   = help: add `#![feature(const_raw_ptr_to_usize_cast)]` to the crate attributes to enable
 
 error[E0019]: constant contains unimplemented expression type
   --> $DIR/match-test-ptr-null.rs:6:15

src/test/ui/consts/min_const_fn/allow_const_fn_ptr_feature_gate.stderr

@@ -5,7 +5,7 @@ LL | #[rustc_allow_const_fn_ptr]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(rustc_attrs)] to the crate attributes to enable
+   = help: add `#![feature(rustc_attrs)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/consts/min_const_fn/min_const_fn_unsafe.stderr

@@ -5,7 +5,7 @@ LL | const fn bad_const_fn_deref_raw(x: *mut usize) -> &'static usize { unsafe {
    |                                                                             ^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51911
-   = help: add #![feature(const_raw_ptr_deref)] to the crate attributes to enable
+   = help: add `#![feature(const_raw_ptr_deref)]` to the crate attributes to enable
 
 error[E0658]: dereferencing raw pointers in constant functions is unstable
   --> $DIR/min_const_fn_unsafe.rs:53:70
@@ -14,7 +14,7 @@ LL | const unsafe fn bad_const_unsafe_deref_raw(x: *mut usize) -> usize { *x }
    |                                                                      ^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51911
-   = help: add #![feature(const_raw_ptr_deref)] to the crate attributes to enable
+   = help: add `#![feature(const_raw_ptr_deref)]` to the crate attributes to enable
 
 error[E0658]: dereferencing raw pointers in constant functions is unstable
   --> $DIR/min_const_fn_unsafe.rs:56:83
@@ -23,7 +23,7 @@ LL | const unsafe fn bad_const_unsafe_deref_raw_ref(x: *mut usize) -> &'static u
    |                                                                                   ^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51911
-   = help: add #![feature(const_raw_ptr_deref)] to the crate attributes to enable
+   = help: add `#![feature(const_raw_ptr_deref)]` to the crate attributes to enable
 
 error[E0658]: unions in const fn are unstable
   --> $DIR/min_const_fn_unsafe.rs:63:5
@@ -32,7 +32,7 @@ LL |     Foo { x: () }.y
    |     ^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51909
-   = help: add #![feature(const_fn_union)] to the crate attributes to enable
+   = help: add `#![feature(const_fn_union)]` to the crate attributes to enable
 
 error[E0133]: dereference of raw pointer is unsafe and requires unsafe function or block
   --> $DIR/min_const_fn_unsafe.rs:50:77

src/test/ui/consts/projection_qualif.stderr

@@ -17,7 +17,7 @@ LL |         unsafe { *b = 5; }
    |                  ^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51911
-   = help: add #![feature(const_raw_ptr_deref)] to the crate attributes to enable
+   = help: add `#![feature(const_raw_ptr_deref)]` to the crate attributes to enable
 
 error: aborting due to 3 previous errors
 

src/test/ui/custom_attribute.stderr

@@ -5,7 +5,7 @@ LL | #[foo]
    |   ^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `foo` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/custom_attribute.rs:5:7
@@ -14,7 +14,7 @@ LL |     #[foo]
    |       ^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `foo` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/custom_attribute.rs:7:7
@@ -23,7 +23,7 @@ LL |     #[foo]
    |       ^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error: aborting due to 3 previous errors
 

src/test/ui/enum-discriminant/feature-gate-arbitrary_enum_discriminant.stderr

@@ -5,7 +5,7 @@ LL |   Tuple() = 2,
    |             ^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/60553
-   = help: add #![feature(arbitrary_enum_discriminant)] to the crate attributes to enable
+   = help: add `#![feature(arbitrary_enum_discriminant)]` to the crate attributes to enable
 
 error[E0658]: discriminants on non-unit variants are experimental
   --> $DIR/feature-gate-arbitrary_enum_discriminant.rs:8:14
@@ -14,7 +14,7 @@ LL |   Struct{} = 3,
    |              ^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/60553
-   = help: add #![feature(arbitrary_enum_discriminant)] to the crate attributes to enable
+   = help: add `#![feature(arbitrary_enum_discriminant)]` to the crate attributes to enable
 
 error[E0658]: custom discriminant values are not allowed in enums with tuple or struct variants
   --> $DIR/feature-gate-arbitrary_enum_discriminant.rs:4:10
@@ -29,7 +29,7 @@ LL |   Struct{} = 3,
    |   ------------ struct variant defined here
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/60553
-   = help: add #![feature(arbitrary_enum_discriminant)] to the crate attributes to enable
+   = help: add `#![feature(arbitrary_enum_discriminant)]` to the crate attributes to enable
 
 error: aborting due to 3 previous errors
 

src/test/ui/error-codes/E0395.stderr

@@ -5,7 +5,7 @@ LL | static BAZ: bool = unsafe { (&FOO as *const i32) == (&BAR as *const i32) };
    |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/53020
-   = help: add #![feature(const_compare_raw_pointers)] to the crate attributes to enable
+   = help: add `#![feature(const_compare_raw_pointers)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/error-codes/E0396.stderr

@@ -5,7 +5,7 @@ LL | const VALUE: u8 = unsafe { *REG_ADDR };
    |                            ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51911
-   = help: add #![feature(const_raw_ptr_deref)] to the crate attributes to enable
+   = help: add `#![feature(const_raw_ptr_deref)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/error-codes/E0658.stderr

@@ -7,7 +7,7 @@ LL | | }
    | |_^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/35118
-   = help: add #![feature(repr128)] to the crate attributes to enable
+   = help: add `#![feature(repr128)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/existential-type/issue-60371.stderr

@@ -5,7 +5,7 @@ LL |     existential type Item: Bug;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/34511
-   = help: add #![feature(existential_type)] to the crate attributes to enable
+   = help: add `#![feature(existential_type)]` to the crate attributes to enable
 
 error[E0277]: the trait bound `(): Bug` is not satisfied
   --> $DIR/issue-60371.rs:8:5

src/test/ui/explore-issue-38412.stderr

@@ -5,7 +5,7 @@ LL |     let Record { a_stable_pub: _, a_unstable_declared_pub: _, a_unstable_un
    |                                                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38412
-   = help: add #![feature(unstable_undeclared)] to the crate attributes to enable
+   = help: add `#![feature(unstable_undeclared)]` to the crate attributes to enable
 
 error[E0658]: use of unstable library feature 'unstable_undeclared'
   --> $DIR/explore-issue-38412.rs:30:5
@@ -14,7 +14,7 @@ LL |     r.a_unstable_undeclared_pub;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38412
-   = help: add #![feature(unstable_undeclared)] to the crate attributes to enable
+   = help: add `#![feature(unstable_undeclared)]` to the crate attributes to enable
 
 error[E0616]: field `b_crate` of struct `pub_and_stability::Record` is private
   --> $DIR/explore-issue-38412.rs:31:5
@@ -41,7 +41,7 @@ LL |     t.2;
    |     ^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38412
-   = help: add #![feature(unstable_undeclared)] to the crate attributes to enable
+   = help: add `#![feature(unstable_undeclared)]` to the crate attributes to enable
 
 error[E0616]: field `3` of struct `pub_and_stability::Tuple` is private
   --> $DIR/explore-issue-38412.rs:38:5
@@ -68,7 +68,7 @@ LL |     r.unstable_undeclared_trait_method();
    |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38412
-   = help: add #![feature(unstable_undeclared)] to the crate attributes to enable
+   = help: add `#![feature(unstable_undeclared)]` to the crate attributes to enable
 
 error[E0658]: use of unstable library feature 'unstable_undeclared'
   --> $DIR/explore-issue-38412.rs:48:7
@@ -77,7 +77,7 @@ LL |     r.unstable_undeclared();
    |       ^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38412
-   = help: add #![feature(unstable_undeclared)] to the crate attributes to enable
+   = help: add `#![feature(unstable_undeclared)]` to the crate attributes to enable
 
 error[E0624]: method `pub_crate` is private
   --> $DIR/explore-issue-38412.rs:50:7
@@ -104,7 +104,7 @@ LL |     t.unstable_undeclared_trait_method();
    |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38412
-   = help: add #![feature(unstable_undeclared)] to the crate attributes to enable
+   = help: add `#![feature(unstable_undeclared)]` to the crate attributes to enable
 
 error[E0658]: use of unstable library feature 'unstable_undeclared'
   --> $DIR/explore-issue-38412.rs:61:7
@@ -113,7 +113,7 @@ LL |     t.unstable_undeclared();
    |       ^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38412
-   = help: add #![feature(unstable_undeclared)] to the crate attributes to enable
+   = help: add `#![feature(unstable_undeclared)]` to the crate attributes to enable
 
 error[E0624]: method `pub_crate` is private
   --> $DIR/explore-issue-38412.rs:63:7

src/test/ui/feature-gate-optimize_attribute.rs

@@ -1,17 +1,17 @@
 #![crate_type="rlib"]
-#![optimize(speed)] //~ ERROR #[optimize] attribute is an unstable feature
+#![optimize(speed)] //~ ERROR `#[optimize]` attribute is an unstable feature
 
-#[optimize(size)] //~ ERROR #[optimize] attribute is an unstable feature
+#[optimize(size)] //~ ERROR `#[optimize]` attribute is an unstable feature
 mod module {
 
-#[optimize(size)] //~ ERROR #[optimize] attribute is an unstable feature
+#[optimize(size)] //~ ERROR `#[optimize]` attribute is an unstable feature
 fn size() {}
 
-#[optimize(speed)] //~ ERROR #[optimize] attribute is an unstable feature
+#[optimize(speed)] //~ ERROR `#[optimize]` attribute is an unstable feature
 fn speed() {}
 
 #[optimize(banana)]
-//~^ ERROR #[optimize] attribute is an unstable feature
+//~^ ERROR `#[optimize]` attribute is an unstable feature
 //~| ERROR E0722
 fn not_known() {}
 

src/test/ui/feature-gate-optimize_attribute.stderr

@@ -1,47 +1,47 @@
-error[E0658]: #[optimize] attribute is an unstable feature
+error[E0658]: `#[optimize]` attribute is an unstable feature
   --> $DIR/feature-gate-optimize_attribute.rs:7:1
    |
 LL | #[optimize(size)]
    | ^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/54882
-   = help: add #![feature(optimize_attribute)] to the crate attributes to enable
+   = help: add `#![feature(optimize_attribute)]` to the crate attributes to enable
 
-error[E0658]: #[optimize] attribute is an unstable feature
+error[E0658]: `#[optimize]` attribute is an unstable feature
   --> $DIR/feature-gate-optimize_attribute.rs:10:1
    |
 LL | #[optimize(speed)]
    | ^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/54882
-   = help: add #![feature(optimize_attribute)] to the crate attributes to enable
+   = help: add `#![feature(optimize_attribute)]` to the crate attributes to enable
 
-error[E0658]: #[optimize] attribute is an unstable feature
+error[E0658]: `#[optimize]` attribute is an unstable feature
   --> $DIR/feature-gate-optimize_attribute.rs:13:1
    |
 LL | #[optimize(banana)]
    | ^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/54882
-   = help: add #![feature(optimize_attribute)] to the crate attributes to enable
+   = help: add `#![feature(optimize_attribute)]` to the crate attributes to enable
 
-error[E0658]: #[optimize] attribute is an unstable feature
+error[E0658]: `#[optimize]` attribute is an unstable feature
   --> $DIR/feature-gate-optimize_attribute.rs:4:1
    |
 LL | #[optimize(size)]
    | ^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/54882
-   = help: add #![feature(optimize_attribute)] to the crate attributes to enable
+   = help: add `#![feature(optimize_attribute)]` to the crate attributes to enable
 
-error[E0658]: #[optimize] attribute is an unstable feature
+error[E0658]: `#[optimize]` attribute is an unstable feature
   --> $DIR/feature-gate-optimize_attribute.rs:2:1
    |
 LL | #![optimize(speed)]
    | ^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/54882
-   = help: add #![feature(optimize_attribute)] to the crate attributes to enable
+   = help: add `#![feature(optimize_attribute)]` to the crate attributes to enable
 
 error[E0722]: invalid argument
   --> $DIR/feature-gate-optimize_attribute.rs:13:12

src/test/ui/feature-gate/await-macro.stderr

@@ -5,7 +5,7 @@ LL |     await!(bar());
    |     ^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/50547
-   = help: add #![feature(await_macro)] to the crate attributes to enable
+   = help: add `#![feature(await_macro)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gate/feature-gate-c_variadic.stderr

@@ -5,7 +5,7 @@ LL | pub unsafe extern "C" fn test(_: i32, ap: ...) { }
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44930
-   = help: add #![feature(c_variadic)] to the crate attributes to enable
+   = help: add `#![feature(c_variadic)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gate/feature-gate-cfg_doctest.stderr

@@ -5,7 +5,7 @@ LL | #[cfg(doctest)]
    |       ^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/62210
-   = help: add #![feature(cfg_doctest)] to the crate attributes to enable
+   = help: add `#![feature(cfg_doctest)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gate/feature-gate-static-nobundle-2.stderr

@@ -1,7 +1,7 @@
 error[E0658]: kind="static-nobundle" is feature gated
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/37403
-   = help: add #![feature(static_nobundle)] to the crate attributes to enable
+   = help: add `#![feature(static_nobundle)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gate/issue-49983-see-issue-0.stderr

@@ -4,7 +4,7 @@ error[E0658]: use of unstable library feature 'ptr_internals': use NonNull inste
 LL | #[allow(unused_imports)] use core::ptr::Unique;
    |                              ^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(ptr_internals)] to the crate attributes to enable
+   = help: add `#![feature(ptr_internals)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gated-feature-in-macro-arg.stderr

@@ -6,7 +6,7 @@ LL | |             fn atomic_fence();
 LL | |         }
    | |_________^
    |
-   = help: add #![feature(intrinsics)] to the crate attributes to enable
+   = help: add `#![feature(intrinsics)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-abi-msp430-interrupt.stderr

@@ -5,7 +5,7 @@ LL | extern "msp430-interrupt" fn foo() {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38487
-   = help: add #![feature(abi_msp430_interrupt)] to the crate attributes to enable
+   = help: add `#![feature(abi_msp430_interrupt)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-abi.stderr

@@ -4,7 +4,7 @@ error[E0658]: intrinsics are subject to change
 LL | extern "rust-intrinsic" fn f1() {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(intrinsics)] to the crate attributes to enable
+   = help: add `#![feature(intrinsics)]` to the crate attributes to enable
 
 error[E0658]: platform intrinsics are experimental and possibly buggy
   --> $DIR/feature-gate-abi.rs:13:1
@@ -13,7 +13,7 @@ LL | extern "platform-intrinsic" fn f2() {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/27731
-   = help: add #![feature(platform_intrinsics)] to the crate attributes to enable
+   = help: add `#![feature(platform_intrinsics)]` to the crate attributes to enable
 
 error[E0658]: vectorcall is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:14:1
@@ -21,7 +21,7 @@ error[E0658]: vectorcall is experimental and subject to change
 LL | extern "vectorcall" fn f3() {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(abi_vectorcall)] to the crate attributes to enable
+   = help: add `#![feature(abi_vectorcall)]` to the crate attributes to enable
 
 error[E0658]: rust-call ABI is subject to change
   --> $DIR/feature-gate-abi.rs:15:1
@@ -30,7 +30,7 @@ LL | extern "rust-call" fn f4() {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29625
-   = help: add #![feature(unboxed_closures)] to the crate attributes to enable
+   = help: add `#![feature(unboxed_closures)]` to the crate attributes to enable
 
 error[E0658]: msp430-interrupt ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:16:1
@@ -39,7 +39,7 @@ LL | extern "msp430-interrupt" fn f5() {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38487
-   = help: add #![feature(abi_msp430_interrupt)] to the crate attributes to enable
+   = help: add `#![feature(abi_msp430_interrupt)]` to the crate attributes to enable
 
 error[E0658]: PTX ABIs are experimental and subject to change
   --> $DIR/feature-gate-abi.rs:17:1
@@ -48,7 +48,7 @@ LL | extern "ptx-kernel" fn f6() {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38788
-   = help: add #![feature(abi_ptx)] to the crate attributes to enable
+   = help: add `#![feature(abi_ptx)]` to the crate attributes to enable
 
 error[E0658]: x86-interrupt ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:18:1
@@ -57,7 +57,7 @@ LL | extern "x86-interrupt" fn f7() {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/40180
-   = help: add #![feature(abi_x86_interrupt)] to the crate attributes to enable
+   = help: add `#![feature(abi_x86_interrupt)]` to the crate attributes to enable
 
 error[E0658]: thiscall is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:19:1
@@ -65,7 +65,7 @@ error[E0658]: thiscall is experimental and subject to change
 LL | extern "thiscall" fn f8() {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(abi_thiscall)] to the crate attributes to enable
+   = help: add `#![feature(abi_thiscall)]` to the crate attributes to enable
 
 error[E0658]: amdgpu-kernel ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:20:1
@@ -74,7 +74,7 @@ LL | extern "amdgpu-kernel" fn f9() {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51575
-   = help: add #![feature(abi_amdgpu_kernel)] to the crate attributes to enable
+   = help: add `#![feature(abi_amdgpu_kernel)]` to the crate attributes to enable
 
 error[E0658]: intrinsics are subject to change
   --> $DIR/feature-gate-abi.rs:24:5
@@ -82,7 +82,7 @@ error[E0658]: intrinsics are subject to change
 LL |     extern "rust-intrinsic" fn m1();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(intrinsics)] to the crate attributes to enable
+   = help: add `#![feature(intrinsics)]` to the crate attributes to enable
 
 error[E0658]: platform intrinsics are experimental and possibly buggy
   --> $DIR/feature-gate-abi.rs:25:5
@@ -91,7 +91,7 @@ LL |     extern "platform-intrinsic" fn m2();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/27731
-   = help: add #![feature(platform_intrinsics)] to the crate attributes to enable
+   = help: add `#![feature(platform_intrinsics)]` to the crate attributes to enable
 
 error[E0658]: vectorcall is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:26:5
@@ -99,7 +99,7 @@ error[E0658]: vectorcall is experimental and subject to change
 LL |     extern "vectorcall" fn m3();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(abi_vectorcall)] to the crate attributes to enable
+   = help: add `#![feature(abi_vectorcall)]` to the crate attributes to enable
 
 error[E0658]: rust-call ABI is subject to change
   --> $DIR/feature-gate-abi.rs:27:5
@@ -108,7 +108,7 @@ LL |     extern "rust-call" fn m4();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29625
-   = help: add #![feature(unboxed_closures)] to the crate attributes to enable
+   = help: add `#![feature(unboxed_closures)]` to the crate attributes to enable
 
 error[E0658]: msp430-interrupt ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:28:5
@@ -117,7 +117,7 @@ LL |     extern "msp430-interrupt" fn m5();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38487
-   = help: add #![feature(abi_msp430_interrupt)] to the crate attributes to enable
+   = help: add `#![feature(abi_msp430_interrupt)]` to the crate attributes to enable
 
 error[E0658]: PTX ABIs are experimental and subject to change
   --> $DIR/feature-gate-abi.rs:29:5
@@ -126,7 +126,7 @@ LL |     extern "ptx-kernel" fn m6();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38788
-   = help: add #![feature(abi_ptx)] to the crate attributes to enable
+   = help: add `#![feature(abi_ptx)]` to the crate attributes to enable
 
 error[E0658]: x86-interrupt ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:30:5
@@ -135,7 +135,7 @@ LL |     extern "x86-interrupt" fn m7();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/40180
-   = help: add #![feature(abi_x86_interrupt)] to the crate attributes to enable
+   = help: add `#![feature(abi_x86_interrupt)]` to the crate attributes to enable
 
 error[E0658]: thiscall is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:31:5
@@ -143,7 +143,7 @@ error[E0658]: thiscall is experimental and subject to change
 LL |     extern "thiscall" fn m8();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(abi_thiscall)] to the crate attributes to enable
+   = help: add `#![feature(abi_thiscall)]` to the crate attributes to enable
 
 error[E0658]: amdgpu-kernel ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:32:5
@@ -152,7 +152,7 @@ LL |     extern "amdgpu-kernel" fn m9();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51575
-   = help: add #![feature(abi_amdgpu_kernel)] to the crate attributes to enable
+   = help: add `#![feature(abi_amdgpu_kernel)]` to the crate attributes to enable
 
 error[E0658]: intrinsics are subject to change
   --> $DIR/feature-gate-abi.rs:34:5
@@ -160,7 +160,7 @@ error[E0658]: intrinsics are subject to change
 LL |     extern "rust-intrinsic" fn dm1() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(intrinsics)] to the crate attributes to enable
+   = help: add `#![feature(intrinsics)]` to the crate attributes to enable
 
 error[E0658]: platform intrinsics are experimental and possibly buggy
   --> $DIR/feature-gate-abi.rs:35:5
@@ -169,7 +169,7 @@ LL |     extern "platform-intrinsic" fn dm2() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/27731
-   = help: add #![feature(platform_intrinsics)] to the crate attributes to enable
+   = help: add `#![feature(platform_intrinsics)]` to the crate attributes to enable
 
 error[E0658]: vectorcall is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:36:5
@@ -177,7 +177,7 @@ error[E0658]: vectorcall is experimental and subject to change
 LL |     extern "vectorcall" fn dm3() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(abi_vectorcall)] to the crate attributes to enable
+   = help: add `#![feature(abi_vectorcall)]` to the crate attributes to enable
 
 error[E0658]: rust-call ABI is subject to change
   --> $DIR/feature-gate-abi.rs:37:5
@@ -186,7 +186,7 @@ LL |     extern "rust-call" fn dm4() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29625
-   = help: add #![feature(unboxed_closures)] to the crate attributes to enable
+   = help: add `#![feature(unboxed_closures)]` to the crate attributes to enable
 
 error[E0658]: msp430-interrupt ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:38:5
@@ -195,7 +195,7 @@ LL |     extern "msp430-interrupt" fn dm5() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38487
-   = help: add #![feature(abi_msp430_interrupt)] to the crate attributes to enable
+   = help: add `#![feature(abi_msp430_interrupt)]` to the crate attributes to enable
 
 error[E0658]: PTX ABIs are experimental and subject to change
   --> $DIR/feature-gate-abi.rs:39:5
@@ -204,7 +204,7 @@ LL |     extern "ptx-kernel" fn dm6() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38788
-   = help: add #![feature(abi_ptx)] to the crate attributes to enable
+   = help: add `#![feature(abi_ptx)]` to the crate attributes to enable
 
 error[E0658]: x86-interrupt ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:40:5
@@ -213,7 +213,7 @@ LL |     extern "x86-interrupt" fn dm7() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/40180
-   = help: add #![feature(abi_x86_interrupt)] to the crate attributes to enable
+   = help: add `#![feature(abi_x86_interrupt)]` to the crate attributes to enable
 
 error[E0658]: thiscall is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:41:5
@@ -221,7 +221,7 @@ error[E0658]: thiscall is experimental and subject to change
 LL |     extern "thiscall" fn dm8() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(abi_thiscall)] to the crate attributes to enable
+   = help: add `#![feature(abi_thiscall)]` to the crate attributes to enable
 
 error[E0658]: amdgpu-kernel ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:42:5
@@ -230,7 +230,7 @@ LL |     extern "amdgpu-kernel" fn dm9() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51575
-   = help: add #![feature(abi_amdgpu_kernel)] to the crate attributes to enable
+   = help: add `#![feature(abi_amdgpu_kernel)]` to the crate attributes to enable
 
 error[E0658]: intrinsics are subject to change
   --> $DIR/feature-gate-abi.rs:49:5
@@ -238,7 +238,7 @@ error[E0658]: intrinsics are subject to change
 LL |     extern "rust-intrinsic" fn m1() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(intrinsics)] to the crate attributes to enable
+   = help: add `#![feature(intrinsics)]` to the crate attributes to enable
 
 error[E0658]: platform intrinsics are experimental and possibly buggy
   --> $DIR/feature-gate-abi.rs:50:5
@@ -247,7 +247,7 @@ LL |     extern "platform-intrinsic" fn m2() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/27731
-   = help: add #![feature(platform_intrinsics)] to the crate attributes to enable
+   = help: add `#![feature(platform_intrinsics)]` to the crate attributes to enable
 
 error[E0658]: vectorcall is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:51:5
@@ -255,7 +255,7 @@ error[E0658]: vectorcall is experimental and subject to change
 LL |     extern "vectorcall" fn m3() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(abi_vectorcall)] to the crate attributes to enable
+   = help: add `#![feature(abi_vectorcall)]` to the crate attributes to enable
 
 error[E0658]: rust-call ABI is subject to change
   --> $DIR/feature-gate-abi.rs:52:5
@@ -264,7 +264,7 @@ LL |     extern "rust-call" fn m4() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29625
-   = help: add #![feature(unboxed_closures)] to the crate attributes to enable
+   = help: add `#![feature(unboxed_closures)]` to the crate attributes to enable
 
 error[E0658]: msp430-interrupt ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:53:5
@@ -273,7 +273,7 @@ LL |     extern "msp430-interrupt" fn m5() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38487
-   = help: add #![feature(abi_msp430_interrupt)] to the crate attributes to enable
+   = help: add `#![feature(abi_msp430_interrupt)]` to the crate attributes to enable
 
 error[E0658]: PTX ABIs are experimental and subject to change
   --> $DIR/feature-gate-abi.rs:54:5
@@ -282,7 +282,7 @@ LL |     extern "ptx-kernel" fn m6() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38788
-   = help: add #![feature(abi_ptx)] to the crate attributes to enable
+   = help: add `#![feature(abi_ptx)]` to the crate attributes to enable
 
 error[E0658]: x86-interrupt ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:55:5
@@ -291,7 +291,7 @@ LL |     extern "x86-interrupt" fn m7() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/40180
-   = help: add #![feature(abi_x86_interrupt)] to the crate attributes to enable
+   = help: add `#![feature(abi_x86_interrupt)]` to the crate attributes to enable
 
 error[E0658]: thiscall is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:56:5
@@ -299,7 +299,7 @@ error[E0658]: thiscall is experimental and subject to change
 LL |     extern "thiscall" fn m8() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(abi_thiscall)] to the crate attributes to enable
+   = help: add `#![feature(abi_thiscall)]` to the crate attributes to enable
 
 error[E0658]: amdgpu-kernel ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:57:5
@@ -308,7 +308,7 @@ LL |     extern "amdgpu-kernel" fn m9() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51575
-   = help: add #![feature(abi_amdgpu_kernel)] to the crate attributes to enable
+   = help: add `#![feature(abi_amdgpu_kernel)]` to the crate attributes to enable
 
 error[E0658]: intrinsics are subject to change
   --> $DIR/feature-gate-abi.rs:62:5
@@ -316,7 +316,7 @@ error[E0658]: intrinsics are subject to change
 LL |     extern "rust-intrinsic" fn im1() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(intrinsics)] to the crate attributes to enable
+   = help: add `#![feature(intrinsics)]` to the crate attributes to enable
 
 error[E0658]: platform intrinsics are experimental and possibly buggy
   --> $DIR/feature-gate-abi.rs:63:5
@@ -325,7 +325,7 @@ LL |     extern "platform-intrinsic" fn im2() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/27731
-   = help: add #![feature(platform_intrinsics)] to the crate attributes to enable
+   = help: add `#![feature(platform_intrinsics)]` to the crate attributes to enable
 
 error[E0658]: vectorcall is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:64:5
@@ -333,7 +333,7 @@ error[E0658]: vectorcall is experimental and subject to change
 LL |     extern "vectorcall" fn im3() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(abi_vectorcall)] to the crate attributes to enable
+   = help: add `#![feature(abi_vectorcall)]` to the crate attributes to enable
 
 error[E0658]: rust-call ABI is subject to change
   --> $DIR/feature-gate-abi.rs:65:5
@@ -342,7 +342,7 @@ LL |     extern "rust-call" fn im4() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29625
-   = help: add #![feature(unboxed_closures)] to the crate attributes to enable
+   = help: add `#![feature(unboxed_closures)]` to the crate attributes to enable
 
 error[E0658]: msp430-interrupt ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:66:5
@@ -351,7 +351,7 @@ LL |     extern "msp430-interrupt" fn im5() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38487
-   = help: add #![feature(abi_msp430_interrupt)] to the crate attributes to enable
+   = help: add `#![feature(abi_msp430_interrupt)]` to the crate attributes to enable
 
 error[E0658]: PTX ABIs are experimental and subject to change
   --> $DIR/feature-gate-abi.rs:67:5
@@ -360,7 +360,7 @@ LL |     extern "ptx-kernel" fn im6() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38788
-   = help: add #![feature(abi_ptx)] to the crate attributes to enable
+   = help: add `#![feature(abi_ptx)]` to the crate attributes to enable
 
 error[E0658]: x86-interrupt ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:68:5
@@ -369,7 +369,7 @@ LL |     extern "x86-interrupt" fn im7() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/40180
-   = help: add #![feature(abi_x86_interrupt)] to the crate attributes to enable
+   = help: add `#![feature(abi_x86_interrupt)]` to the crate attributes to enable
 
 error[E0658]: thiscall is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:69:5
@@ -377,7 +377,7 @@ error[E0658]: thiscall is experimental and subject to change
 LL |     extern "thiscall" fn im8() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(abi_thiscall)] to the crate attributes to enable
+   = help: add `#![feature(abi_thiscall)]` to the crate attributes to enable
 
 error[E0658]: amdgpu-kernel ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:70:5
@@ -386,7 +386,7 @@ LL |     extern "amdgpu-kernel" fn im9() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51575
-   = help: add #![feature(abi_amdgpu_kernel)] to the crate attributes to enable
+   = help: add `#![feature(abi_amdgpu_kernel)]` to the crate attributes to enable
 
 error[E0658]: intrinsics are subject to change
   --> $DIR/feature-gate-abi.rs:74:11
@@ -394,7 +394,7 @@ error[E0658]: intrinsics are subject to change
 LL | type A1 = extern "rust-intrinsic" fn();
    |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(intrinsics)] to the crate attributes to enable
+   = help: add `#![feature(intrinsics)]` to the crate attributes to enable
 
 error[E0658]: platform intrinsics are experimental and possibly buggy
   --> $DIR/feature-gate-abi.rs:75:11
@@ -403,7 +403,7 @@ LL | type A2 = extern "platform-intrinsic" fn();
    |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/27731
-   = help: add #![feature(platform_intrinsics)] to the crate attributes to enable
+   = help: add `#![feature(platform_intrinsics)]` to the crate attributes to enable
 
 error[E0658]: vectorcall is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:76:11
@@ -411,7 +411,7 @@ error[E0658]: vectorcall is experimental and subject to change
 LL | type A3 = extern "vectorcall" fn();
    |           ^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(abi_vectorcall)] to the crate attributes to enable
+   = help: add `#![feature(abi_vectorcall)]` to the crate attributes to enable
 
 error[E0658]: rust-call ABI is subject to change
   --> $DIR/feature-gate-abi.rs:77:11
@@ -420,7 +420,7 @@ LL | type A4 = extern "rust-call" fn();
    |           ^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29625
-   = help: add #![feature(unboxed_closures)] to the crate attributes to enable
+   = help: add `#![feature(unboxed_closures)]` to the crate attributes to enable
 
 error[E0658]: msp430-interrupt ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:78:11
@@ -429,7 +429,7 @@ LL | type A5 = extern "msp430-interrupt" fn();
    |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38487
-   = help: add #![feature(abi_msp430_interrupt)] to the crate attributes to enable
+   = help: add `#![feature(abi_msp430_interrupt)]` to the crate attributes to enable
 
 error[E0658]: PTX ABIs are experimental and subject to change
   --> $DIR/feature-gate-abi.rs:79:11
@@ -438,7 +438,7 @@ LL | type A6 = extern "ptx-kernel" fn ();
    |           ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38788
-   = help: add #![feature(abi_ptx)] to the crate attributes to enable
+   = help: add `#![feature(abi_ptx)]` to the crate attributes to enable
 
 error[E0658]: x86-interrupt ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:80:11
@@ -447,7 +447,7 @@ LL | type A7 = extern "x86-interrupt" fn();
    |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/40180
-   = help: add #![feature(abi_x86_interrupt)] to the crate attributes to enable
+   = help: add `#![feature(abi_x86_interrupt)]` to the crate attributes to enable
 
 error[E0658]: thiscall is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:81:11
@@ -455,7 +455,7 @@ error[E0658]: thiscall is experimental and subject to change
 LL | type A8 = extern "thiscall" fn();
    |           ^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(abi_thiscall)] to the crate attributes to enable
+   = help: add `#![feature(abi_thiscall)]` to the crate attributes to enable
 
 error[E0658]: amdgpu-kernel ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:82:11
@@ -464,7 +464,7 @@ LL | type A9 = extern "amdgpu-kernel" fn();
    |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51575
-   = help: add #![feature(abi_amdgpu_kernel)] to the crate attributes to enable
+   = help: add `#![feature(abi_amdgpu_kernel)]` to the crate attributes to enable
 
 error[E0658]: intrinsics are subject to change
   --> $DIR/feature-gate-abi.rs:85:1
@@ -472,7 +472,7 @@ error[E0658]: intrinsics are subject to change
 LL | extern "rust-intrinsic" {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(intrinsics)] to the crate attributes to enable
+   = help: add `#![feature(intrinsics)]` to the crate attributes to enable
 
 error[E0658]: platform intrinsics are experimental and possibly buggy
   --> $DIR/feature-gate-abi.rs:86:1
@@ -481,7 +481,7 @@ LL | extern "platform-intrinsic" {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/27731
-   = help: add #![feature(platform_intrinsics)] to the crate attributes to enable
+   = help: add `#![feature(platform_intrinsics)]` to the crate attributes to enable
 
 error[E0658]: vectorcall is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:87:1
@@ -489,7 +489,7 @@ error[E0658]: vectorcall is experimental and subject to change
 LL | extern "vectorcall" {}
    | ^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(abi_vectorcall)] to the crate attributes to enable
+   = help: add `#![feature(abi_vectorcall)]` to the crate attributes to enable
 
 error[E0658]: rust-call ABI is subject to change
   --> $DIR/feature-gate-abi.rs:88:1
@@ -498,7 +498,7 @@ LL | extern "rust-call" {}
    | ^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29625
-   = help: add #![feature(unboxed_closures)] to the crate attributes to enable
+   = help: add `#![feature(unboxed_closures)]` to the crate attributes to enable
 
 error[E0658]: msp430-interrupt ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:89:1
@@ -507,7 +507,7 @@ LL | extern "msp430-interrupt" {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38487
-   = help: add #![feature(abi_msp430_interrupt)] to the crate attributes to enable
+   = help: add `#![feature(abi_msp430_interrupt)]` to the crate attributes to enable
 
 error[E0658]: PTX ABIs are experimental and subject to change
   --> $DIR/feature-gate-abi.rs:90:1
@@ -516,7 +516,7 @@ LL | extern "ptx-kernel" {}
    | ^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/38788
-   = help: add #![feature(abi_ptx)] to the crate attributes to enable
+   = help: add `#![feature(abi_ptx)]` to the crate attributes to enable
 
 error[E0658]: x86-interrupt ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:91:1
@@ -525,7 +525,7 @@ LL | extern "x86-interrupt" {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/40180
-   = help: add #![feature(abi_x86_interrupt)] to the crate attributes to enable
+   = help: add `#![feature(abi_x86_interrupt)]` to the crate attributes to enable
 
 error[E0658]: thiscall is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:92:1
@@ -533,7 +533,7 @@ error[E0658]: thiscall is experimental and subject to change
 LL | extern "thiscall" {}
    | ^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(abi_thiscall)] to the crate attributes to enable
+   = help: add `#![feature(abi_thiscall)]` to the crate attributes to enable
 
 error[E0658]: amdgpu-kernel ABI is experimental and subject to change
   --> $DIR/feature-gate-abi.rs:93:1
@@ -542,7 +542,7 @@ LL | extern "amdgpu-kernel" {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51575
-   = help: add #![feature(abi_amdgpu_kernel)] to the crate attributes to enable
+   = help: add `#![feature(abi_amdgpu_kernel)]` to the crate attributes to enable
 
 error: aborting due to 63 previous errors
 

src/test/ui/feature-gates/feature-gate-abi_unadjusted.stderr

@@ -6,7 +6,7 @@ LL | |
 LL | | }
    | |_^
    |
-   = help: add #![feature(abi_unadjusted)] to the crate attributes to enable
+   = help: add `#![feature(abi_unadjusted)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-alloc-error-handler.rs

@@ -5,7 +5,7 @@
 
 use core::alloc::Layout;
 
-#[alloc_error_handler] //~ ERROR #[alloc_error_handler] is an unstable feature
+#[alloc_error_handler] //~ ERROR `#[alloc_error_handler]` is an unstable feature
 fn oom(info: Layout) -> ! {
     loop {}
 }

src/test/ui/feature-gates/feature-gate-alloc-error-handler.stderr

@@ -1,11 +1,11 @@
-error[E0658]: #[alloc_error_handler] is an unstable feature
+error[E0658]: `#[alloc_error_handler]` is an unstable feature
   --> $DIR/feature-gate-alloc-error-handler.rs:8:1
    |
 LL | #[alloc_error_handler]
    | ^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51540
-   = help: add #![feature(alloc_error_handler)] to the crate attributes to enable
+   = help: add `#![feature(alloc_error_handler)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-allocator_internals.stderr

@@ -4,7 +4,7 @@ error[E0658]: the `#[default_lib_allocator]` attribute is an experimental featur
 LL | #![default_lib_allocator]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(allocator_internals)] to the crate attributes to enable
+   = help: add `#![feature(allocator_internals)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-allow-internal-unsafe-nested-macro.stderr

@@ -7,7 +7,7 @@ LL |         #[allow_internal_unsafe]
 LL | bar!();
    | ------- in this macro invocation
    |
-   = help: add #![feature(allow_internal_unsafe)] to the crate attributes to enable
+   = help: add `#![feature(allow_internal_unsafe)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-allow-internal-unstable-nested-macro.stderr

@@ -7,7 +7,7 @@ LL |         #[allow_internal_unstable()]
 LL | bar!();
    | ------- in this macro invocation
    |
-   = help: add #![feature(allow_internal_unstable)] to the crate attributes to enable
+   = help: add `#![feature(allow_internal_unstable)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-allow-internal-unstable-struct.stderr

@@ -4,7 +4,7 @@ error[E0658]: allow_internal_unstable side-steps feature gating and stability ch
 LL | #[allow_internal_unstable()]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(allow_internal_unstable)] to the crate attributes to enable
+   = help: add `#![feature(allow_internal_unstable)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-allow-internal-unstable.stderr

@@ -4,7 +4,7 @@ error[E0658]: allow_internal_unstable side-steps feature gating and stability ch
 LL | #[allow_internal_unstable()]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(allow_internal_unstable)] to the crate attributes to enable
+   = help: add `#![feature(allow_internal_unstable)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-allow_fail.stderr

@@ -5,7 +5,7 @@ LL | #[allow_fail]
    | ^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/46488
-   = help: add #![feature(allow_fail)] to the crate attributes to enable
+   = help: add `#![feature(allow_fail)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-arbitrary-self-types.stderr

@@ -5,7 +5,7 @@ LL |     fn foo(self: Ptr<Self>);
    |                  ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44874
-   = help: add #![feature(arbitrary_self_types)] to the crate attributes to enable
+   = help: add `#![feature(arbitrary_self_types)]` to the crate attributes to enable
    = help: consider changing to `self`, `&self`, `&mut self`, or `self: Box<Self>`
 
 error[E0658]: `Ptr<Bar>` cannot be used as the type of `self` without the `arbitrary_self_types` feature
@@ -15,7 +15,7 @@ LL |     fn foo(self: Ptr<Self>) {}
    |                  ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44874
-   = help: add #![feature(arbitrary_self_types)] to the crate attributes to enable
+   = help: add `#![feature(arbitrary_self_types)]` to the crate attributes to enable
    = help: consider changing to `self`, `&self`, `&mut self`, or `self: Box<Self>`
 
 error[E0658]: `std::boxed::Box<Ptr<Bar>>` cannot be used as the type of `self` without the `arbitrary_self_types` feature
@@ -25,7 +25,7 @@ LL |     fn bar(self: Box<Ptr<Self>>) {}
    |                  ^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44874
-   = help: add #![feature(arbitrary_self_types)] to the crate attributes to enable
+   = help: add `#![feature(arbitrary_self_types)]` to the crate attributes to enable
    = help: consider changing to `self`, `&self`, `&mut self`, or `self: Box<Self>`
 
 error: aborting due to 3 previous errors

src/test/ui/feature-gates/feature-gate-arbitrary_self_types-raw-pointer.stderr

@@ -5,7 +5,7 @@ LL |     fn bar(self: *const Self);
    |                  ^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44874
-   = help: add #![feature(arbitrary_self_types)] to the crate attributes to enable
+   = help: add `#![feature(arbitrary_self_types)]` to the crate attributes to enable
    = help: consider changing to `self`, `&self`, `&mut self`, or `self: Box<Self>`
 
 error[E0658]: `*const Foo` cannot be used as the type of `self` without the `arbitrary_self_types` feature
@@ -15,7 +15,7 @@ LL |     fn foo(self: *const Self) {}
    |                  ^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44874
-   = help: add #![feature(arbitrary_self_types)] to the crate attributes to enable
+   = help: add `#![feature(arbitrary_self_types)]` to the crate attributes to enable
    = help: consider changing to `self`, `&self`, `&mut self`, or `self: Box<Self>`
 
 error[E0658]: `*const ()` cannot be used as the type of `self` without the `arbitrary_self_types` feature
@@ -25,7 +25,7 @@ LL |     fn bar(self: *const Self) {}
    |                  ^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44874
-   = help: add #![feature(arbitrary_self_types)] to the crate attributes to enable
+   = help: add `#![feature(arbitrary_self_types)]` to the crate attributes to enable
    = help: consider changing to `self`, `&self`, `&mut self`, or `self: Box<Self>`
 
 error: aborting due to 3 previous errors

src/test/ui/feature-gates/feature-gate-asm.stderr

@@ -5,7 +5,7 @@ LL |         asm!("");
    |         ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29722
-   = help: add #![feature(asm)] to the crate attributes to enable
+   = help: add `#![feature(asm)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-asm2.stderr

@@ -5,7 +5,7 @@ LL |         println!("{:?}", asm!(""));
    |                          ^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29722
-   = help: add #![feature(asm)] to the crate attributes to enable
+   = help: add `#![feature(asm)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-assoc-type-defaults.stderr

@@ -5,7 +5,7 @@ LL |     type Bar = u8;
    |     ^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29661
-   = help: add #![feature(associated_type_defaults)] to the crate attributes to enable
+   = help: add `#![feature(associated_type_defaults)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-associated_type_bounds.stderr

@@ -5,7 +5,7 @@ LL |     type A: Iterator<Item: Copy>;
    |                      ^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/52662
-   = help: add #![feature(associated_type_bounds)] to the crate attributes to enable
+   = help: add `#![feature(associated_type_bounds)]` to the crate attributes to enable
 
 error[E0658]: associated type bounds are unstable
   --> $DIR/feature-gate-associated_type_bounds.rs:15:22
@@ -14,7 +14,7 @@ LL |     type B: Iterator<Item: 'static>;
    |                      ^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/52662
-   = help: add #![feature(associated_type_bounds)] to the crate attributes to enable
+   = help: add `#![feature(associated_type_bounds)]` to the crate attributes to enable
 
 error[E0658]: associated type bounds are unstable
   --> $DIR/feature-gate-associated_type_bounds.rs:19:20
@@ -23,7 +23,7 @@ LL | struct _St1<T: Tr1<As1: Tr2>> {
    |                    ^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/52662
-   = help: add #![feature(associated_type_bounds)] to the crate attributes to enable
+   = help: add `#![feature(associated_type_bounds)]` to the crate attributes to enable
 
 error[E0658]: associated type bounds are unstable
   --> $DIR/feature-gate-associated_type_bounds.rs:26:18
@@ -32,7 +32,7 @@ LL | enum _En1<T: Tr1<As1: Tr2>> {
    |                  ^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/52662
-   = help: add #![feature(associated_type_bounds)] to the crate attributes to enable
+   = help: add `#![feature(associated_type_bounds)]` to the crate attributes to enable
 
 error[E0658]: associated type bounds are unstable
   --> $DIR/feature-gate-associated_type_bounds.rs:33:19
@@ -41,7 +41,7 @@ LL | union _Un1<T: Tr1<As1: Tr2>> {
    |                   ^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/52662
-   = help: add #![feature(associated_type_bounds)] to the crate attributes to enable
+   = help: add `#![feature(associated_type_bounds)]` to the crate attributes to enable
 
 error[E0658]: associated type bounds are unstable
   --> $DIR/feature-gate-associated_type_bounds.rs:40:37
@@ -50,7 +50,7 @@ LL | type _TaWhere1<T> where T: Iterator<Item: Copy> = T;
    |                                     ^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/52662
-   = help: add #![feature(associated_type_bounds)] to the crate attributes to enable
+   = help: add `#![feature(associated_type_bounds)]` to the crate attributes to enable
 
 error[E0658]: associated type bounds are unstable
   --> $DIR/feature-gate-associated_type_bounds.rs:43:22
@@ -59,7 +59,7 @@ LL | fn _apit(_: impl Tr1<As1: Copy>) {}
    |                      ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/52662
-   = help: add #![feature(associated_type_bounds)] to the crate attributes to enable
+   = help: add `#![feature(associated_type_bounds)]` to the crate attributes to enable
 
 error[E0658]: associated type bounds are unstable
   --> $DIR/feature-gate-associated_type_bounds.rs:45:26
@@ -68,7 +68,7 @@ LL | fn _apit_dyn(_: &dyn Tr1<As1: Copy>) {}
    |                          ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/52662
-   = help: add #![feature(associated_type_bounds)] to the crate attributes to enable
+   = help: add `#![feature(associated_type_bounds)]` to the crate attributes to enable
 
 error[E0658]: associated type bounds are unstable
   --> $DIR/feature-gate-associated_type_bounds.rs:48:24
@@ -77,7 +77,7 @@ LL | fn _rpit() -> impl Tr1<As1: Copy> { S1 }
    |                        ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/52662
-   = help: add #![feature(associated_type_bounds)] to the crate attributes to enable
+   = help: add `#![feature(associated_type_bounds)]` to the crate attributes to enable
 
 error[E0658]: associated type bounds are unstable
   --> $DIR/feature-gate-associated_type_bounds.rs:51:31
@@ -86,7 +86,7 @@ LL | fn _rpit_dyn() -> Box<dyn Tr1<As1: Copy>> { Box::new(S1) }
    |                               ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/52662
-   = help: add #![feature(associated_type_bounds)] to the crate attributes to enable
+   = help: add `#![feature(associated_type_bounds)]` to the crate attributes to enable
 
 error[E0658]: associated type bounds are unstable
   --> $DIR/feature-gate-associated_type_bounds.rs:54:23
@@ -95,7 +95,7 @@ LL | const _cdef: impl Tr1<As1: Copy> = S1;
    |                       ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/52662
-   = help: add #![feature(associated_type_bounds)] to the crate attributes to enable
+   = help: add `#![feature(associated_type_bounds)]` to the crate attributes to enable
 
 error[E0658]: associated type bounds are unstable
   --> $DIR/feature-gate-associated_type_bounds.rs:60:24
@@ -104,7 +104,7 @@ LL | static _sdef: impl Tr1<As1: Copy> = S1;
    |                        ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/52662
-   = help: add #![feature(associated_type_bounds)] to the crate attributes to enable
+   = help: add `#![feature(associated_type_bounds)]` to the crate attributes to enable
 
 error[E0658]: associated type bounds are unstable
   --> $DIR/feature-gate-associated_type_bounds.rs:67:21
@@ -113,7 +113,7 @@ LL |     let _: impl Tr1<As1: Copy> = S1;
    |                     ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/52662
-   = help: add #![feature(associated_type_bounds)] to the crate attributes to enable
+   = help: add `#![feature(associated_type_bounds)]` to the crate attributes to enable
 
 error[E0562]: `impl Trait` not allowed outside of function and inherent method return types
   --> $DIR/feature-gate-associated_type_bounds.rs:54:14

src/test/ui/feature-gates/feature-gate-async-await-2015-edition.stderr

@@ -23,7 +23,7 @@ LL | async fn foo() {}
    | ^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/50547
-   = help: add #![feature(async_await)] to the crate attributes to enable
+   = help: add `#![feature(async_await)]` to the crate attributes to enable
 
 error: aborting due to 4 previous errors
 

src/test/ui/feature-gates/feature-gate-async-await.stderr

@@ -11,7 +11,7 @@ LL |     async fn foo() {}
    |     ^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/50547
-   = help: add #![feature(async_await)] to the crate attributes to enable
+   = help: add `#![feature(async_await)]` to the crate attributes to enable
 
 error[E0658]: async fn is unstable
   --> $DIR/feature-gate-async-await.rs:10:5
@@ -20,7 +20,7 @@ LL |     async fn foo();
    |     ^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/50547
-   = help: add #![feature(async_await)] to the crate attributes to enable
+   = help: add `#![feature(async_await)]` to the crate attributes to enable
 
 error[E0658]: async fn is unstable
   --> $DIR/feature-gate-async-await.rs:14:1
@@ -29,7 +29,7 @@ LL | async fn foo() {}
    | ^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/50547
-   = help: add #![feature(async_await)] to the crate attributes to enable
+   = help: add `#![feature(async_await)]` to the crate attributes to enable
 
 error[E0658]: async blocks are unstable
   --> $DIR/feature-gate-async-await.rs:17:13
@@ -38,7 +38,7 @@ LL |     let _ = async {};
    |             ^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/50547
-   = help: add #![feature(async_await)] to the crate attributes to enable
+   = help: add `#![feature(async_await)]` to the crate attributes to enable
 
 error: aborting due to 5 previous errors
 

src/test/ui/feature-gates/feature-gate-box-expr.stderr

@@ -5,7 +5,7 @@ LL |     let x = box 'c';
    |             ^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/49733
-   = help: add #![feature(box_syntax)] to the crate attributes to enable
+   = help: add `#![feature(box_syntax)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-box_patterns.stderr

@@ -5,7 +5,7 @@ LL |     let box x = Box::new('c');
    |         ^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29641
-   = help: add #![feature(box_patterns)] to the crate attributes to enable
+   = help: add `#![feature(box_patterns)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-box_syntax.stderr

@@ -5,7 +5,7 @@ LL |     let x = box 3;
    |             ^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/49733
-   = help: add #![feature(box_syntax)] to the crate attributes to enable
+   = help: add `#![feature(box_syntax)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-cfg-target-has-atomic.stderr

@@ -5,7 +5,7 @@ LL | #[cfg(target_has_atomic = "8")]
    |       ^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/32976
-   = help: add #![feature(cfg_target_has_atomic)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_has_atomic)]` to the crate attributes to enable
 
 error[E0658]: `cfg(target_has_atomic)` is experimental and subject to change
   --> $DIR/feature-gate-cfg-target-has-atomic.rs:21:7
@@ -14,7 +14,7 @@ LL | #[cfg(target_has_atomic = "8")]
    |       ^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/32976
-   = help: add #![feature(cfg_target_has_atomic)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_has_atomic)]` to the crate attributes to enable
 
 error[E0658]: `cfg(target_has_atomic)` is experimental and subject to change
   --> $DIR/feature-gate-cfg-target-has-atomic.rs:26:7
@@ -23,7 +23,7 @@ LL | #[cfg(target_has_atomic = "16")]
    |       ^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/32976
-   = help: add #![feature(cfg_target_has_atomic)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_has_atomic)]` to the crate attributes to enable
 
 error[E0658]: `cfg(target_has_atomic)` is experimental and subject to change
   --> $DIR/feature-gate-cfg-target-has-atomic.rs:31:7
@@ -32,7 +32,7 @@ LL | #[cfg(target_has_atomic = "16")]
    |       ^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/32976
-   = help: add #![feature(cfg_target_has_atomic)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_has_atomic)]` to the crate attributes to enable
 
 error[E0658]: `cfg(target_has_atomic)` is experimental and subject to change
   --> $DIR/feature-gate-cfg-target-has-atomic.rs:36:7
@@ -41,7 +41,7 @@ LL | #[cfg(target_has_atomic = "32")]
    |       ^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/32976
-   = help: add #![feature(cfg_target_has_atomic)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_has_atomic)]` to the crate attributes to enable
 
 error[E0658]: `cfg(target_has_atomic)` is experimental and subject to change
   --> $DIR/feature-gate-cfg-target-has-atomic.rs:41:7
@@ -50,7 +50,7 @@ LL | #[cfg(target_has_atomic = "32")]
    |       ^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/32976
-   = help: add #![feature(cfg_target_has_atomic)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_has_atomic)]` to the crate attributes to enable
 
 error[E0658]: `cfg(target_has_atomic)` is experimental and subject to change
   --> $DIR/feature-gate-cfg-target-has-atomic.rs:46:7
@@ -59,7 +59,7 @@ LL | #[cfg(target_has_atomic = "64")]
    |       ^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/32976
-   = help: add #![feature(cfg_target_has_atomic)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_has_atomic)]` to the crate attributes to enable
 
 error[E0658]: `cfg(target_has_atomic)` is experimental and subject to change
   --> $DIR/feature-gate-cfg-target-has-atomic.rs:51:7
@@ -68,7 +68,7 @@ LL | #[cfg(target_has_atomic = "64")]
    |       ^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/32976
-   = help: add #![feature(cfg_target_has_atomic)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_has_atomic)]` to the crate attributes to enable
 
 error[E0658]: `cfg(target_has_atomic)` is experimental and subject to change
   --> $DIR/feature-gate-cfg-target-has-atomic.rs:56:7
@@ -77,7 +77,7 @@ LL | #[cfg(target_has_atomic = "128")]
    |       ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/32976
-   = help: add #![feature(cfg_target_has_atomic)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_has_atomic)]` to the crate attributes to enable
 
 error[E0658]: `cfg(target_has_atomic)` is experimental and subject to change
   --> $DIR/feature-gate-cfg-target-has-atomic.rs:61:7
@@ -86,7 +86,7 @@ LL | #[cfg(target_has_atomic = "128")]
    |       ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/32976
-   = help: add #![feature(cfg_target_has_atomic)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_has_atomic)]` to the crate attributes to enable
 
 error[E0658]: `cfg(target_has_atomic)` is experimental and subject to change
   --> $DIR/feature-gate-cfg-target-has-atomic.rs:66:7
@@ -95,7 +95,7 @@ LL | #[cfg(target_has_atomic = "ptr")]
    |       ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/32976
-   = help: add #![feature(cfg_target_has_atomic)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_has_atomic)]` to the crate attributes to enable
 
 error[E0658]: `cfg(target_has_atomic)` is experimental and subject to change
   --> $DIR/feature-gate-cfg-target-has-atomic.rs:71:7
@@ -104,7 +104,7 @@ LL | #[cfg(target_has_atomic = "ptr")]
    |       ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/32976
-   = help: add #![feature(cfg_target_has_atomic)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_has_atomic)]` to the crate attributes to enable
 
 error[E0658]: `cfg(target_has_atomic)` is experimental and subject to change
   --> $DIR/feature-gate-cfg-target-has-atomic.rs:78:10
@@ -113,7 +113,7 @@ LL |     cfg!(target_has_atomic = "8");
    |          ^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/32976
-   = help: add #![feature(cfg_target_has_atomic)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_has_atomic)]` to the crate attributes to enable
 
 error[E0658]: `cfg(target_has_atomic)` is experimental and subject to change
   --> $DIR/feature-gate-cfg-target-has-atomic.rs:80:10
@@ -122,7 +122,7 @@ LL |     cfg!(target_has_atomic = "16");
    |          ^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/32976
-   = help: add #![feature(cfg_target_has_atomic)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_has_atomic)]` to the crate attributes to enable
 
 error[E0658]: `cfg(target_has_atomic)` is experimental and subject to change
   --> $DIR/feature-gate-cfg-target-has-atomic.rs:82:10
@@ -131,7 +131,7 @@ LL |     cfg!(target_has_atomic = "32");
    |          ^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/32976
-   = help: add #![feature(cfg_target_has_atomic)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_has_atomic)]` to the crate attributes to enable
 
 error[E0658]: `cfg(target_has_atomic)` is experimental and subject to change
   --> $DIR/feature-gate-cfg-target-has-atomic.rs:84:10
@@ -140,7 +140,7 @@ LL |     cfg!(target_has_atomic = "64");
    |          ^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/32976
-   = help: add #![feature(cfg_target_has_atomic)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_has_atomic)]` to the crate attributes to enable
 
 error[E0658]: `cfg(target_has_atomic)` is experimental and subject to change
   --> $DIR/feature-gate-cfg-target-has-atomic.rs:86:10
@@ -149,7 +149,7 @@ LL |     cfg!(target_has_atomic = "128");
    |          ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/32976
-   = help: add #![feature(cfg_target_has_atomic)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_has_atomic)]` to the crate attributes to enable
 
 error[E0658]: `cfg(target_has_atomic)` is experimental and subject to change
   --> $DIR/feature-gate-cfg-target-has-atomic.rs:88:10
@@ -158,7 +158,7 @@ LL |     cfg!(target_has_atomic = "ptr");
    |          ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/32976
-   = help: add #![feature(cfg_target_has_atomic)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_has_atomic)]` to the crate attributes to enable
 
 error: aborting due to 18 previous errors
 

src/test/ui/feature-gates/feature-gate-cfg-target-thread-local.stderr

@@ -5,7 +5,7 @@ LL |     #[cfg_attr(target_thread_local, thread_local)]
    |                ^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29594
-   = help: add #![feature(cfg_target_thread_local)] to the crate attributes to enable
+   = help: add `#![feature(cfg_target_thread_local)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-compiler-builtins.stderr

@@ -4,7 +4,7 @@ error[E0658]: the `#[compiler_builtins]` attribute is used to identify the `comp
 LL | #![compiler_builtins]
    | ^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(compiler_builtins)] to the crate attributes to enable
+   = help: add `#![feature(compiler_builtins)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-concat_idents.stderr

@@ -5,7 +5,7 @@ LL |     let a = concat_idents!(X, Y_1);
    |             ^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29599
-   = help: add #![feature(concat_idents)] to the crate attributes to enable
+   = help: add `#![feature(concat_idents)]` to the crate attributes to enable
 
 error[E0658]: use of unstable library feature 'concat_idents': `concat_idents` is not stable enough for use and is subject to change
   --> $DIR/feature-gate-concat_idents.rs:6:13
@@ -14,7 +14,7 @@ LL |     let b = concat_idents!(X, Y_2);
    |             ^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29599
-   = help: add #![feature(concat_idents)] to the crate attributes to enable
+   = help: add `#![feature(concat_idents)]` to the crate attributes to enable
 
 error: aborting due to 2 previous errors
 

src/test/ui/feature-gates/feature-gate-concat_idents2.stderr

@@ -5,7 +5,7 @@ LL |     concat_idents!(a, b);
    |     ^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29599
-   = help: add #![feature(concat_idents)] to the crate attributes to enable
+   = help: add `#![feature(concat_idents)]` to the crate attributes to enable
 
 error[E0425]: cannot find value `ab` in this scope
   --> $DIR/feature-gate-concat_idents2.rs:4:5

src/test/ui/feature-gates/feature-gate-concat_idents3.stderr

@@ -5,7 +5,7 @@ LL |     assert_eq!(10, concat_idents!(X, Y_1));
    |                    ^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29599
-   = help: add #![feature(concat_idents)] to the crate attributes to enable
+   = help: add `#![feature(concat_idents)]` to the crate attributes to enable
 
 error[E0658]: use of unstable library feature 'concat_idents': `concat_idents` is not stable enough for use and is subject to change
   --> $DIR/feature-gate-concat_idents3.rs:8:20
@@ -14,7 +14,7 @@ LL |     assert_eq!(20, concat_idents!(X, Y_2));
    |                    ^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29599
-   = help: add #![feature(concat_idents)] to the crate attributes to enable
+   = help: add `#![feature(concat_idents)]` to the crate attributes to enable
 
 error: aborting due to 2 previous errors
 

src/test/ui/feature-gates/feature-gate-const_fn.stderr

@@ -23,7 +23,7 @@ LL |     const fn foo() -> u32;
    |     ^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/57563
-   = help: add #![feature(const_fn)] to the crate attributes to enable
+   = help: add `#![feature(const_fn)]` to the crate attributes to enable
 
 error[E0658]: const fn is unstable
   --> $DIR/feature-gate-const_fn.rs:8:5
@@ -32,7 +32,7 @@ LL |     const fn bar() -> u32 { 0 }
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/57563
-   = help: add #![feature(const_fn)] to the crate attributes to enable
+   = help: add `#![feature(const_fn)]` to the crate attributes to enable
 
 error: aborting due to 5 previous errors
 

src/test/ui/feature-gates/feature-gate-const_generics.stderr

@@ -5,7 +5,7 @@ LL | fn foo<const X: ()>() {}
    |              ^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44580
-   = help: add #![feature(const_generics)] to the crate attributes to enable
+   = help: add `#![feature(const_generics)]` to the crate attributes to enable
 
 error[E0658]: const generics are unstable
   --> $DIR/feature-gate-const_generics.rs:3:18
@@ -14,7 +14,7 @@ LL | struct Foo<const X: usize>([(); X]);
    |                  ^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44580
-   = help: add #![feature(const_generics)] to the crate attributes to enable
+   = help: add `#![feature(const_generics)]` to the crate attributes to enable
 
 error: aborting due to 2 previous errors
 

src/test/ui/feature-gates/feature-gate-const_transmute.stderr

@@ -5,7 +5,7 @@ LL | const TRANSMUTED_U32: u32 = unsafe { mem::transmute(Foo(3)) };
    |                                      ^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/53605
-   = help: add #![feature(const_transmute)] to the crate attributes to enable
+   = help: add `#![feature(const_transmute)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-crate_visibility_modifier.stderr

@@ -5,7 +5,7 @@ LL | crate struct Bender {
    | ^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/53120
-   = help: add #![feature(crate_visibility_modifier)] to the crate attributes to enable
+   = help: add `#![feature(crate_visibility_modifier)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-custom_attribute.stderr

@@ -5,7 +5,7 @@ LL | #[fake_attr]
    |   ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute.rs:8:3
@@ -14,7 +14,7 @@ LL | #[fake_attr(100)]
    |   ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute.rs:9:3
@@ -23,7 +23,7 @@ LL | #[fake_attr(1, 2, 3)]
    |   ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute.rs:10:3
@@ -32,7 +32,7 @@ LL | #[fake_attr("hello")]
    |   ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute.rs:11:3
@@ -41,7 +41,7 @@ LL | #[fake_attr(name = "hello")]
    |   ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute.rs:12:3
@@ -50,7 +50,7 @@ LL | #[fake_attr(1, "hi", key = 12, true, false)]
    |   ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute.rs:13:3
@@ -59,7 +59,7 @@ LL | #[fake_attr(key = "hello", val = 10)]
    |   ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute.rs:14:3
@@ -68,7 +68,7 @@ LL | #[fake_attr(key("hello"), val(10))]
    |   ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute.rs:15:3
@@ -77,7 +77,7 @@ LL | #[fake_attr(enabled = true, disabled = false)]
    |   ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute.rs:16:3
@@ -86,7 +86,7 @@ LL | #[fake_attr(true)]
    |   ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute.rs:17:3
@@ -95,7 +95,7 @@ LL | #[fake_attr(pi = 3.14159)]
    |   ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute.rs:18:3
@@ -104,7 +104,7 @@ LL | #[fake_attr(b"hi")]
    |   ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `fake_doc` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute.rs:19:3
@@ -113,7 +113,7 @@ LL | #[fake_doc(r"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
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error: aborting due to 13 previous errors
 

src/test/ui/feature-gates/feature-gate-custom_attribute2.stderr

@@ -5,7 +5,7 @@ LL | struct StLt<#[lt_struct] 'a>(&'a u32);
    |             ^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `ty_struct` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute2.rs:8:13
@@ -14,7 +14,7 @@ LL | struct StTy<#[ty_struct] I>(I);
    |             ^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `lt_enum` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute2.rs:11:11
@@ -23,7 +23,7 @@ LL | enum EnLt<#[lt_enum] 'b> { A(&'b u32), B }
    |           ^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `ty_enum` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute2.rs:13:11
@@ -32,7 +32,7 @@ LL | enum EnTy<#[ty_enum] J> { A(J), B }
    |           ^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `lt_trait` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute2.rs:16:12
@@ -41,7 +41,7 @@ LL | trait TrLt<#[lt_trait] 'c> { fn foo(&self, _: &'c [u32]) -> &'c u32; }
    |            ^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `ty_trait` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute2.rs:18:12
@@ -50,7 +50,7 @@ LL | trait TrTy<#[ty_trait] K> { fn foo(&self, _: K); }
    |            ^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `lt_type` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute2.rs:21:11
@@ -59,7 +59,7 @@ LL | type TyLt<#[lt_type] 'd> = &'d u32;
    |           ^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `ty_type` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute2.rs:23:11
@@ -68,7 +68,7 @@ LL | type TyTy<#[ty_type] L> = (L, );
    |           ^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `lt_inherent` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute2.rs:26:6
@@ -77,7 +77,7 @@ LL | impl<#[lt_inherent] 'e> StLt<'e> { }
    |      ^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `ty_inherent` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute2.rs:28:6
@@ -86,7 +86,7 @@ LL | impl<#[ty_inherent] M> StTy<M> { }
    |      ^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `lt_impl_for` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute2.rs:31:6
@@ -95,7 +95,7 @@ LL | impl<#[lt_impl_for] 'f> TrLt<'f> for StLt<'f> {
    |      ^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `ty_impl_for` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute2.rs:35:6
@@ -104,7 +104,7 @@ LL | impl<#[ty_impl_for] N> TrTy<N> for StTy<N> {
    |      ^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `lt_fn` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute2.rs:40:9
@@ -113,7 +113,7 @@ LL | fn f_lt<#[lt_fn] 'g>(_: &'g [u32]) -> &'g u32 { loop { } }
    |         ^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `ty_fn` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute2.rs:42:9
@@ -122,7 +122,7 @@ LL | fn f_ty<#[ty_fn] O>(_: O) { }
    |         ^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `lt_meth` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute2.rs:46:13
@@ -131,7 +131,7 @@ LL |     fn m_lt<#[lt_meth] 'h>(_: &'h [u32]) -> &'h u32 { loop { } }
    |             ^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `ty_meth` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute2.rs:48:13
@@ -140,7 +140,7 @@ LL |     fn m_ty<#[ty_meth] P>(_: P) { }
    |             ^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error[E0658]: The attribute `lt_hof` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-custom_attribute2.rs:53:19
@@ -149,7 +149,7 @@ LL |     where Q: for <#[lt_hof] 'i> Fn(&'i [u32]) -> &'i u32
    |                   ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
-   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+   = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
 error: aborting due to 17 previous errors
 

src/test/ui/feature-gates/feature-gate-custom_test_frameworks.stderr

@@ -5,7 +5,7 @@ LL | #[test_case]
    | ^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/50297
-   = help: add #![feature(custom_test_frameworks)] to the crate attributes to enable
+   = help: add `#![feature(custom_test_frameworks)]` to the crate attributes to enable
 
 error[E0658]: custom test frameworks are an unstable feature
   --> $DIR/feature-gate-custom_test_frameworks.rs:1:1
@@ -14,7 +14,7 @@ LL | #![test_runner(main)]
    | ^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/50297
-   = help: add #![feature(custom_test_frameworks)] to the crate attributes to enable
+   = help: add `#![feature(custom_test_frameworks)]` to the crate attributes to enable
 
 error: aborting due to 2 previous errors
 

src/test/ui/feature-gates/feature-gate-decl_macro.stderr

@@ -5,7 +5,7 @@ LL | macro m() {}
    | ^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/39412
-   = help: add #![feature(decl_macro)] to the crate attributes to enable
+   = help: add `#![feature(decl_macro)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-doc_alias.rs

@@ -1,4 +1,4 @@
-#[doc(alias = "foo")] //~ ERROR: #[doc(alias = "...")] is experimental
+#[doc(alias = "foo")] //~ ERROR: `#[doc(alias = "...")]` is experimental
 pub struct Foo;
 
 fn main() {}

src/test/ui/feature-gates/feature-gate-doc_alias.stderr

@@ -1,11 +1,11 @@
-error[E0658]: #[doc(alias = "...")] is experimental
+error[E0658]: `#[doc(alias = "...")]` is experimental
   --> $DIR/feature-gate-doc_alias.rs:1:1
    |
 LL | #[doc(alias = "foo")]
    | ^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/50146
-   = help: add #![feature(doc_alias)] to the crate attributes to enable
+   = help: add `#![feature(doc_alias)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-doc_cfg-cfg-rustdoc.stderr

@@ -5,7 +5,7 @@ LL | #[cfg(rustdoc)]
    |       ^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/43781
-   = help: add #![feature(doc_cfg)] to the crate attributes to enable
+   = help: add `#![feature(doc_cfg)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-doc_cfg.rs

@@ -1,2 +1,2 @@
-#[doc(cfg(unix))] //~ ERROR: #[doc(cfg(...))] is experimental
+#[doc(cfg(unix))] //~ ERROR: `#[doc(cfg(...))]` is experimental
 fn main() {}

src/test/ui/feature-gates/feature-gate-doc_cfg.stderr

@@ -1,11 +1,11 @@
-error[E0658]: #[doc(cfg(...))] is experimental
+error[E0658]: `#[doc(cfg(...))]` is experimental
   --> $DIR/feature-gate-doc_cfg.rs:1:1
    |
 LL | #[doc(cfg(unix))]
    | ^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/43781
-   = help: add #![feature(doc_cfg)] to the crate attributes to enable
+   = help: add `#![feature(doc_cfg)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-doc_keyword.rs

@@ -1,4 +1,4 @@
-#[doc(keyword = "match")] //~ ERROR: #[doc(keyword = "...")] is experimental
+#[doc(keyword = "match")] //~ ERROR: `#[doc(keyword = "...")]` is experimental
 /// wonderful
 mod foo{}
 

src/test/ui/feature-gates/feature-gate-doc_keyword.stderr

@@ -1,11 +1,11 @@
-error[E0658]: #[doc(keyword = "...")] is experimental
+error[E0658]: `#[doc(keyword = "...")]` is experimental
   --> $DIR/feature-gate-doc_keyword.rs:1:1
    |
 LL | #[doc(keyword = "match")]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/51315
-   = help: add #![feature(doc_keyword)] to the crate attributes to enable
+   = help: add `#![feature(doc_keyword)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-doc_masked.rs

@@ -1,4 +1,4 @@
-#[doc(masked)] //~ ERROR: #[doc(masked)] is experimental
+#[doc(masked)] //~ ERROR: `#[doc(masked)]` is experimental
 extern crate std as realstd;
 
 fn main() {}

src/test/ui/feature-gates/feature-gate-doc_masked.stderr

@@ -1,11 +1,11 @@
-error[E0658]: #[doc(masked)] is experimental
+error[E0658]: `#[doc(masked)]` is experimental
   --> $DIR/feature-gate-doc_masked.rs:1:1
    |
 LL | #[doc(masked)]
    | ^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44027
-   = help: add #![feature(doc_masked)] to the crate attributes to enable
+   = help: add `#![feature(doc_masked)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-doc_spotlight.rs

@@ -1,4 +1,4 @@
-#[doc(spotlight)] //~ ERROR: #[doc(spotlight)] is experimental
+#[doc(spotlight)] //~ ERROR: `#[doc(spotlight)]` is experimental
 trait SomeTrait {}
 
 fn main() {}

src/test/ui/feature-gates/feature-gate-doc_spotlight.stderr

@@ -1,11 +1,11 @@
-error[E0658]: #[doc(spotlight)] is experimental
+error[E0658]: `#[doc(spotlight)]` is experimental
   --> $DIR/feature-gate-doc_spotlight.rs:1:1
    |
 LL | #[doc(spotlight)]
    | ^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/45040
-   = help: add #![feature(doc_spotlight)] to the crate attributes to enable
+   = help: add `#![feature(doc_spotlight)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-dropck-ugeh.stderr

@@ -5,7 +5,7 @@ LL |     #[unsafe_destructor_blind_to_params] // This is the UGEH attribute
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/28498
-   = help: add #![feature(dropck_parametricity)] to the crate attributes to enable
+   = help: add `#![feature(dropck_parametricity)]` to the crate attributes to enable
 
 warning: use of deprecated attribute `dropck_parametricity`: unsafe_destructor_blind_to_params has been replaced by may_dangle and will be removed in the future. See https://github.com/rust-lang/rust/issues/34761
   --> $DIR/feature-gate-dropck-ugeh.rs:16:5

src/test/ui/feature-gates/feature-gate-exclusive-range-pattern.stderr

@@ -5,7 +5,7 @@ LL |         0 .. 3 => {}
    |         ^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/37854
-   = help: add #![feature(exclusive_range_pattern)] to the crate attributes to enable
+   = help: add `#![feature(exclusive_range_pattern)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-existential-type.stderr

@@ -5,7 +5,7 @@ LL | existential type Foo: std::fmt::Debug;
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/34511
-   = help: add #![feature(existential_type)] to the crate attributes to enable
+   = help: add `#![feature(existential_type)]` to the crate attributes to enable
 
 error[E0658]: existential types are unstable
   --> $DIR/feature-gate-existential-type.rs:11:5
@@ -14,7 +14,7 @@ LL |     existential type Baa: std::fmt::Debug;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/34511
-   = help: add #![feature(existential_type)] to the crate attributes to enable
+   = help: add `#![feature(existential_type)]` to the crate attributes to enable
 
 error: aborting due to 2 previous errors
 

src/test/ui/feature-gates/feature-gate-extern_types.stderr

@@ -5,7 +5,7 @@ LL |     type T;
    |     ^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/43467
-   = help: add #![feature(extern_types)] to the crate attributes to enable
+   = help: add `#![feature(extern_types)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-external_doc.rs

@@ -1,2 +1,2 @@
-#[doc(include="asdf.md")] //~ ERROR: #[doc(include = "...")] is experimental
+#[doc(include="asdf.md")] //~ ERROR: `#[doc(include = "...")]` is experimental
 fn main() {}

src/test/ui/feature-gates/feature-gate-external_doc.stderr

@@ -1,11 +1,11 @@
-error[E0658]: #[doc(include = "...")] is experimental
+error[E0658]: `#[doc(include = "...")]` is experimental
   --> $DIR/feature-gate-external_doc.rs:1:1
    |
 LL | #[doc(include="asdf.md")]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44732
-   = help: add #![feature(external_doc)] to the crate attributes to enable
+   = help: add `#![feature(external_doc)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-ffi_returns_twice.stderr

@@ -5,7 +5,7 @@ LL |     #[ffi_returns_twice]
    |     ^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/58314
-   = help: add #![feature(ffi_returns_twice)] to the crate attributes to enable
+   = help: add `#![feature(ffi_returns_twice)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-format_args_nl.stderr

@@ -4,7 +4,7 @@ error[E0658]: use of unstable library feature 'format_args_nl': `format_args_nl`
 LL |     format_args_nl!("");
    |     ^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(format_args_nl)] to the crate attributes to enable
+   = help: add `#![feature(format_args_nl)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-fundamental.stderr

@@ -5,7 +5,7 @@ LL | #[fundamental]
    | ^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/29635
-   = help: add #![feature(fundamental)] to the crate attributes to enable
+   = help: add `#![feature(fundamental)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-generators.stderr

@@ -5,7 +5,7 @@ LL |     yield true;
    |     ^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/43122
-   = help: add #![feature(generators)] to the crate attributes to enable
+   = help: add `#![feature(generators)]` to the crate attributes to enable
 
 error[E0627]: yield statement outside of generator literal
   --> $DIR/feature-gate-generators.rs:2:5

src/test/ui/feature-gates/feature-gate-generic_associated_types.stderr

@@ -5,7 +5,7 @@ LL |     type Pointer<T>: Deref<Target = T>;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44265
-   = help: add #![feature(generic_associated_types)] to the crate attributes to enable
+   = help: add `#![feature(generic_associated_types)]` to the crate attributes to enable
 
 error[E0658]: generic associated types are unstable
   --> $DIR/feature-gate-generic_associated_types.rs:6:5
@@ -14,7 +14,7 @@ LL |     type Pointer2<T>: Deref<Target = T> where T: Clone, U: Clone;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44265
-   = help: add #![feature(generic_associated_types)] to the crate attributes to enable
+   = help: add `#![feature(generic_associated_types)]` to the crate attributes to enable
 
 error[E0658]: where clauses on associated types are unstable
   --> $DIR/feature-gate-generic_associated_types.rs:6:5
@@ -23,7 +23,7 @@ LL |     type Pointer2<T>: Deref<Target = T> where T: Clone, U: Clone;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44265
-   = help: add #![feature(generic_associated_types)] to the crate attributes to enable
+   = help: add `#![feature(generic_associated_types)]` to the crate attributes to enable
 
 error[E0658]: generic associated types are unstable
   --> $DIR/feature-gate-generic_associated_types.rs:14:5
@@ -32,7 +32,7 @@ LL |     type Pointer<Usize> = Box<Usize>;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44265
-   = help: add #![feature(generic_associated_types)] to the crate attributes to enable
+   = help: add `#![feature(generic_associated_types)]` to the crate attributes to enable
 
 error[E0658]: generic associated types are unstable
   --> $DIR/feature-gate-generic_associated_types.rs:16:5
@@ -41,7 +41,7 @@ LL |     type Pointer2<U32> = Box<U32>;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44265
-   = help: add #![feature(generic_associated_types)] to the crate attributes to enable
+   = help: add `#![feature(generic_associated_types)]` to the crate attributes to enable
 
 error[E0658]: where clauses on associated types are unstable
   --> $DIR/feature-gate-generic_associated_types.rs:21:5
@@ -50,7 +50,7 @@ LL |     type Assoc where Self: Sized;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44265
-   = help: add #![feature(generic_associated_types)] to the crate attributes to enable
+   = help: add `#![feature(generic_associated_types)]` to the crate attributes to enable
 
 error[E0658]: where clauses on associated types are unstable
   --> $DIR/feature-gate-generic_associated_types.rs:26:5
@@ -59,7 +59,7 @@ LL |     type Assoc where Self: Sized = Foo;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/44265
-   = help: add #![feature(generic_associated_types)] to the crate attributes to enable
+   = help: add `#![feature(generic_associated_types)]` to the crate attributes to enable
 
 error: aborting due to 7 previous errors
 

src/test/ui/feature-gates/feature-gate-global_asm.stderr

@@ -5,7 +5,7 @@ LL | global_asm!("");
    | ^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/35119
-   = help: add #![feature(global_asm)] to the crate attributes to enable
+   = help: add `#![feature(global_asm)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-intrinsics.stderr

@@ -6,7 +6,7 @@ LL | |     fn bar();
 LL | | }
    | |_^
    |
-   = help: add #![feature(intrinsics)] to the crate attributes to enable
+   = help: add `#![feature(intrinsics)]` to the crate attributes to enable
 
 error[E0658]: intrinsics are subject to change
   --> $DIR/feature-gate-intrinsics.rs:5:1
@@ -14,7 +14,7 @@ error[E0658]: intrinsics are subject to change
 LL | extern "rust-intrinsic" fn baz() {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(intrinsics)] to the crate attributes to enable
+   = help: add `#![feature(intrinsics)]` to the crate attributes to enable
 
 error[E0093]: unrecognized intrinsic function: `bar`
   --> $DIR/feature-gate-intrinsics.rs:2:5

src/test/ui/feature-gates/feature-gate-is_sorted.stderr

@@ -5,7 +5,7 @@ LL |     assert!([1, 2, 2, 9].iter().is_sorted());
    |                                 ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/53485
-   = help: add #![feature(is_sorted)] to the crate attributes to enable
+   = help: add `#![feature(is_sorted)]` to the crate attributes to enable
 
 error[E0658]: use of unstable library feature 'is_sorted': new API
   --> $DIR/feature-gate-is_sorted.rs:5:39
@@ -14,7 +14,7 @@ LL |     assert!(![-2i32, -1, 0, 3].iter().is_sorted_by_key(|n| n.abs()));
    |                                       ^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/53485
-   = help: add #![feature(is_sorted)] to the crate attributes to enable
+   = help: add `#![feature(is_sorted)]` to the crate attributes to enable
 
 error[E0658]: use of unstable library feature 'is_sorted': new API
   --> $DIR/feature-gate-is_sorted.rs:9:26
@@ -23,7 +23,7 @@ LL |     assert!([1, 2, 2, 9].is_sorted());
    |                          ^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/53485
-   = help: add #![feature(is_sorted)] to the crate attributes to enable
+   = help: add `#![feature(is_sorted)]` to the crate attributes to enable
 
 error[E0658]: use of unstable library feature 'is_sorted': new API
   --> $DIR/feature-gate-is_sorted.rs:11:32
@@ -32,7 +32,7 @@ LL |     assert!(![-2i32, -1, 0, 3].is_sorted_by_key(|n| n.abs()));
    |                                ^^^^^^^^^^^^^^^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/53485
-   = help: add #![feature(is_sorted)] to the crate attributes to enable
+   = help: add `#![feature(is_sorted)]` to the crate attributes to enable
 
 error: aborting due to 4 previous errors
 

src/test/ui/feature-gates/feature-gate-label_break_value.stderr

@@ -5,7 +5,7 @@ LL |     'a: {
    |     ^^
    |
    = note: for more information, see https://github.com/rust-lang/rust/issues/48594
-   = help: add #![feature(label_break_value)] to the crate attributes to enable
+   = help: add `#![feature(label_break_value)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/feature-gates/feature-gate-lang-items.stderr

@@ -4,7 +4,7 @@ error[E0658]: language items are subject to change
 LL | #[lang = "foo"]
    | ^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(lang_items)] to the crate attributes to enable
+   = help: add `#![feature(lang_items)]` to the crate attributes to enable
 
 error[E0522]: definition of an unknown language item: `foo`
   --> $DIR/feature-gate-lang-items.rs:1:1