review comments

src/librustc_resolve/macros.rs

@@ -328,7 +328,7 @@ impl<'a> Resolver<'a> {
                 if attr_kind == NonMacroAttrKind::Custom {
                     assert!(path.segments.len() == 1);
                     if !features.custom_attribute {
-                        let msg = format!("the attribute `{}` is currently unknown to the \
+                        let msg = format!("The attribute `{}` is currently unknown to the \
                                             compiler and may have meaning added to it in the \
                                             future", path);
                         self.report_unknown_attribute(

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

@@ -1,4 +1,4 @@
-error[E0658]: the attribute `fixed_stack_segment` is currently unknown to the compiler and may have meaning added to it in the future
+error[E0658]: The attribute `fixed_stack_segment` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/obsolete-attr.rs:5:3
    |
 LL | #[fixed_stack_segment] fn f() {}
@@ -7,7 +7,7 @@ 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
 
-error[E0658]: the attribute `ab_isize` is currently unknown to the compiler and may have meaning added to it in the future
+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
    |
 LL | #[ab_isize="stdcall"] extern {}

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

@@ -1,4 +1,4 @@
-error[E0658]: the attribute `mutable_doc` is currently unknown to the compiler and may have meaning added to it in the future
+error[E0658]: The attribute `mutable_doc` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/unknown-attr.rs:5:4
    |
 LL | #![mutable_doc]
@@ -7,7 +7,7 @@ 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
 
-error[E0658]: the attribute `dance` is currently unknown to the compiler and may have meaning added to it in the future
+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
    |
 LL | #[dance] mod a {}
@@ -16,7 +16,7 @@ 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
 
-error[E0658]: the attribute `dance` is currently unknown to the compiler and may have meaning added to it in the future
+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
    |
 LL | #[dance] fn main() {}

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

@@ -1,4 +1,4 @@
-error[E0658]: the attribute `unknown` is currently unknown to the compiler and may have meaning added to it in the future
+error[E0658]: The attribute `unknown` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/cfg-attr-unknown-attribute-macro-expansion.rs:3:27
    |
 LL |         #[cfg_attr(all(), unknown)]

src/test/ui/custom_attribute.rs

@@ -1,9 +1,9 @@
 #![feature(stmt_expr_attributes)]
 
-#[foo] //~ ERROR the attribute `foo`
+#[foo] //~ ERROR The attribute `foo`
 fn main() {
-    #[foo] //~ ERROR the attribute `foo`
+    #[foo] //~ ERROR The attribute `foo`
     let x = ();
-    #[foo] //~ ERROR the attribute `foo`
+    #[foo] //~ ERROR The attribute `foo`
     x
 }

src/test/ui/custom_attribute.stderr

@@ -1,4 +1,4 @@
-error[E0658]: the attribute `foo` is currently unknown to the compiler and may have meaning added to it in the future
+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:3:3
    |
 LL | #[foo]
@@ -7,7 +7,7 @@ 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
 
-error[E0658]: the attribute `foo` is currently unknown to the compiler and may have meaning added to it in the future
+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
    |
 LL |     #[foo]
@@ -16,7 +16,7 @@ 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
 
-error[E0658]: the attribute `foo` is currently unknown to the compiler and may have meaning added to it in the future
+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
    |
 LL |     #[foo]

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

@@ -1,4 +1,4 @@
-error[E0658]: the attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
+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:7:3
    |
 LL | #[fake_attr]
@@ -7,7 +7,7 @@ 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
 
-error[E0658]: the attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
+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
    |
 LL | #[fake_attr(100)]
@@ -16,7 +16,7 @@ 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
 
-error[E0658]: the attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
+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
    |
 LL | #[fake_attr(1, 2, 3)]
@@ -25,7 +25,7 @@ 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
 
-error[E0658]: the attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
+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
    |
 LL | #[fake_attr("hello")]
@@ -34,7 +34,7 @@ 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
 
-error[E0658]: the attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
+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
    |
 LL | #[fake_attr(name = "hello")]
@@ -43,7 +43,7 @@ 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
 
-error[E0658]: the attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
+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
    |
 LL | #[fake_attr(1, "hi", key = 12, true, false)]
@@ -52,7 +52,7 @@ 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
 
-error[E0658]: the attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
+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
    |
 LL | #[fake_attr(key = "hello", val = 10)]
@@ -61,7 +61,7 @@ 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
 
-error[E0658]: the attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
+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
    |
 LL | #[fake_attr(key("hello"), val(10))]
@@ -70,7 +70,7 @@ 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
 
-error[E0658]: the attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
+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
    |
 LL | #[fake_attr(enabled = true, disabled = false)]
@@ -79,7 +79,7 @@ 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
 
-error[E0658]: the attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
+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
    |
 LL | #[fake_attr(true)]
@@ -88,7 +88,7 @@ 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
 
-error[E0658]: the attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
+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
    |
 LL | #[fake_attr(pi = 3.14159)]
@@ -97,7 +97,7 @@ 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
 
-error[E0658]: the attribute `fake_attr` is currently unknown to the compiler and may have meaning added to it in the future
+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
    |
 LL | #[fake_attr(b"hi")]
@@ -106,7 +106,7 @@ 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
 
-error[E0658]: the attribute `fake_doc` is currently unknown to the compiler and may have meaning added to it in the future
+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
    |
 LL | #[fake_doc(r"doc")]

src/test/ui/feature-gates/feature-gate-rustc-attrs.stderr

@@ -37,7 +37,7 @@ LL | #[rustc_unknown]
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
    = help: add `#![feature(rustc_attrs)]` to the crate attributes to enable
 
-error[E0658]: the attribute `rustc_unknown` is currently unknown to the compiler and may have meaning added to it in the future
+error[E0658]: The attribute `rustc_unknown` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/feature-gate-rustc-attrs.rs:20:3
    |
 LL | #[rustc_unknown]

src/test/ui/issues/issue-32655.stderr

@@ -1,4 +1,4 @@
-error[E0658]: the attribute `derive_Clone` is currently unknown to the compiler and may have meaning added to it in the future
+error[E0658]: The attribute `derive_Clone` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/issue-32655.rs:6:11
    |
 LL |         #[derive_Clone]
@@ -10,7 +10,7 @@ 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
 
-error[E0658]: the attribute `derive_Clone` is currently unknown to the compiler and may have meaning added to it in the future
+error[E0658]: The attribute `derive_Clone` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/issue-32655.rs:18:7
    |
 LL |     #[derive_Clone]

src/test/ui/issues/issue-49074.rs

@@ -1,7 +1,7 @@
 // Check that unknown attribute error is shown even if there are unresolved macros.
 
 #[marco_use] // typo
-//~^ ERROR the attribute `marco_use` is currently unknown to the compiler
+//~^ ERROR The attribute `marco_use` is currently unknown to the compiler
 mod foo {
     macro_rules! bar {
         () => ();

src/test/ui/issues/issue-49074.stderr

@@ -1,4 +1,4 @@
-error[E0658]: the attribute `marco_use` is currently unknown to the compiler and may have meaning added to it in the future
+error[E0658]: The attribute `marco_use` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/issue-49074.rs:3:3
    |
 LL | #[marco_use] // typo

src/test/ui/macros/macro-reexport-removed.stderr

@@ -10,7 +10,7 @@ note: subsumed by `pub use`
 LL | #![feature(macro_reexport)]
    |            ^^^^^^^^^^^^^^
 
-error[E0658]: the attribute `macro_reexport` is currently unknown to the compiler and may have meaning added to it in the future
+error[E0658]: The attribute `macro_reexport` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/macro-reexport-removed.rs:5:3
    |
 LL | #[macro_reexport(macro_one)]

src/test/ui/proc-macro/derive-helper-shadowing.stderr

@@ -1,4 +1,4 @@
-error[E0658]: the attribute `empty_helper` is currently unknown to the compiler and may have meaning added to it in the future
+error[E0658]: The attribute `empty_helper` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/derive-helper-shadowing.rs:22:15
    |
 LL |             #[empty_helper]

src/test/ui/proc-macro/derive-still-gated.stderr

@@ -1,4 +1,4 @@
-error[E0658]: the attribute `derive_Empty` is currently unknown to the compiler and may have meaning added to it in the future
+error[E0658]: The attribute `derive_Empty` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/derive-still-gated.rs:6:3
    |
 LL | #[derive_Empty]

src/test/ui/proc-macro/expand-to-unstable-2.stderr

@@ -7,7 +7,7 @@ LL | #[derive(Unstable)]
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
    = help: add `#![feature(rustc_attrs)]` to the crate attributes to enable
 
-error[E0658]: the attribute `rustc_foo` is currently unknown to the compiler and may have meaning added to it in the future
+error[E0658]: The attribute `rustc_foo` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/expand-to-unstable-2.rs:6:10
    |
 LL | #[derive(Unstable)]

src/test/ui/proc-macro/issue-41211.stderr

@@ -1,4 +1,4 @@
-error[E0658]: the attribute `identity_attr` is currently unknown to the compiler and may have meaning added to it in the future
+error[E0658]: The attribute `identity_attr` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/issue-41211.rs:8:4
    |
 LL | #![identity_attr]

src/test/ui/proc-macro/macro-namespace-reserved-2.stderr

@@ -76,7 +76,7 @@ error: can't use a procedural macro from the same crate that defines it
 LL | #[derive(MyTrait)]
    |          ^^^^^^^
 
-error[E0658]: the attribute `my_macro` is currently unknown to the compiler and may have meaning added to it in the future
+error[E0658]: The attribute `my_macro` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/macro-namespace-reserved-2.rs:38:3
    |
 LL | #[my_macro]

src/test/ui/proc-macro/proc-macro-attributes.stderr

@@ -1,4 +1,4 @@
-error[E0658]: the attribute `C` is currently unknown to the compiler and may have meaning added to it in the future
+error[E0658]: The attribute `C` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/proc-macro-attributes.rs:7:3
    |
 LL | #[C]

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

@@ -1,4 +1,4 @@
-error[E0658]: the attribute `attr_proc_macra` is currently unknown to the compiler and may have meaning added to it in the future
+error[E0658]: The attribute `attr_proc_macra` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/resolve-error.rs:27:3
    |
 LL | #[attr_proc_macra]
@@ -7,7 +7,7 @@ LL | #[attr_proc_macra]
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
    = help: add `#![feature(custom_attribute)]` to the crate attributes to enable
 
-error[E0658]: the attribute `FooWithLongNan` is currently unknown to the compiler and may have meaning added to it in the future
+error[E0658]: The attribute `FooWithLongNan` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/resolve-error.rs:31:3
    |
 LL | #[FooWithLongNan]

src/test/ui/reserved/reserved-attr-on-macro.stderr

@@ -7,7 +7,7 @@ LL | #[rustc_attribute_should_be_reserved]
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
    = help: add `#![feature(rustc_attrs)]` to the crate attributes to enable
 
-error[E0658]: the attribute `rustc_attribute_should_be_reserved` is currently unknown to the compiler and may have meaning added to it in the future
+error[E0658]: The attribute `rustc_attribute_should_be_reserved` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/reserved-attr-on-macro.rs:1:3
    |
 LL | #[rustc_attribute_should_be_reserved]

src/test/ui/span/issue-36530.stderr

@@ -1,4 +1,4 @@
-error[E0658]: the attribute `foo` is currently unknown to the compiler and may have meaning added to it in the future
+error[E0658]: The attribute `foo` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/issue-36530.rs:3:3
    |
 LL | #[foo]
@@ -16,7 +16,7 @@ LL |     #![foo]
    = note: for more information, see https://github.com/rust-lang/rust/issues/54726
    = help: add `#![feature(custom_inner_attributes)]` 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
+error[E0658]: The attribute `foo` is currently unknown to the compiler and may have meaning added to it in the future
   --> $DIR/issue-36530.rs:5:8
    |
 LL |     #![foo]