Rollup merge of #62133 - petrochenkov:norustc, r=eddyb

Feature gate `rustc` attributes harder

Fixes https://github.com/rust-lang/rust/issues/62116

21 files changed, 185 insertions, 161 deletions

diff --git a/src/test/run-pass-fulldeps/issue-15778-pass.rs b/src/test/run-pass-fulldeps/issue-15778-pass.rs
index 2add3ccbe36..35152e7f4ba 100644
--- a/src/test/run-pass-fulldeps/issue-15778-pass.rs
+++ b/src/test/run-pass-fulldeps/issue-15778-pass.rs
@@ -2,7 +2,8 @@
 // ignore-stage1
 // compile-flags: -D crate-not-okay
 
-#![feature(plugin, rustc_attrs)]
+#![feature(plugin, custom_attribute, custom_inner_attributes, rustc_attrs)]
+
 #![plugin(lint_for_crate)]
 #![rustc_crate_okay]
 #![rustc_crate_blue]
@@ -10,4 +11,4 @@
 #![rustc_crate_grey]
 #![rustc_crate_green]
 
-pub fn main() { }
+fn main() {}
diff --git a/src/test/run-pass/attr-on-generic-formals.rs b/src/test/run-pass/attr-on-generic-formals.rs
deleted file mode 100644
index 9ebf0fcb1c1..00000000000
--- a/src/test/run-pass/attr-on-generic-formals.rs
+++ /dev/null
@@ -1,52 +0,0 @@
-#![allow(unused_attributes)]
-
-// This test ensures we can attach attributes to the formals in all
-// places where generic parameter lists occur, assuming appropriate
-// feature gates are enabled.
-//
-// (We are prefixing all tested features with `rustc_`, to ensure that
-// the attributes themselves won't be rejected by the compiler when
-// using `rustc_attrs` feature. There is a separate compile-fail/ test
-// ensuring that the attribute feature-gating works in this context.)
-
-#![feature(rustc_attrs)]
-#![allow(dead_code)]
-
-struct StLt<#[rustc_lt_struct] 'a>(&'a u32);
-struct StTy<#[rustc_ty_struct] I>(I);
-
-enum EnLt<#[rustc_lt_enum] 'b> { A(&'b u32), B }
-enum EnTy<#[rustc_ty_enum] J> { A(J), B }
-
-trait TrLt<#[rustc_lt_trait] 'c> { fn foo(&self, _: &'c [u32]) -> &'c u32; }
-trait TrTy<#[rustc_ty_trait] K> { fn foo(&self, _: K); }
-
-type TyLt<#[rustc_lt_type] 'd> = &'d u32;
-type TyTy<#[rustc_ty_type] L> = (L, );
-
-impl<#[rustc_lt_inherent] 'e> StLt<'e> { }
-impl<#[rustc_ty_inherent] M> StTy<M> { }
-
-impl<#[rustc_lt_impl_for] 'f> TrLt<'f> for StLt<'f> {
-    fn foo(&self, _: &'f [u32]) -> &'f u32 { loop { } }
-}
-impl<#[rustc_ty_impl_for] N> TrTy<N> for StTy<N> {
-    fn foo(&self, _: N) { }
-}
-
-fn f_lt<#[rustc_lt_fn] 'g>(_: &'g [u32]) -> &'g u32 { loop { } }
-fn f_ty<#[rustc_ty_fn] O>(_: O) { }
-
-impl<I> StTy<I> {
-    fn m_lt<#[rustc_lt_meth] 'h>(_: &'h [u32]) -> &'h u32 { loop { } }
-    fn m_ty<#[rustc_ty_meth] P>(_: P) { }
-}
-
-fn hof_lt<Q>(_: Q)
-    where Q: for <#[rustc_lt_hof] 'i> Fn(&'i [u32]) -> &'i u32
-{
-}
-
-fn main() {
-
-}
diff --git a/src/test/ui/attributes/attrs-with-no-formal-in-generics-1.rs b/src/test/ui/attributes/attrs-with-no-formal-in-generics-1.rs
index ca5fdd9da85..df9c8d89465 100644
--- a/src/test/ui/attributes/attrs-with-no-formal-in-generics-1.rs
+++ b/src/test/ui/attributes/attrs-with-no-formal-in-generics-1.rs
@@ -6,10 +6,8 @@
 
 struct RefIntPair<'a, 'b>(&'a u32, &'b u32);
 
-impl<#[rustc_1] 'a, 'b, #[oops]> RefIntPair<'a, 'b> {
+impl<#[rustc_dummy] 'a, 'b, #[oops]> RefIntPair<'a, 'b> {
     //~^ ERROR trailing attribute after generic parameter
 }
 
-fn main() {
-
-}
+fn main() {}
diff --git a/src/test/ui/attributes/attrs-with-no-formal-in-generics-1.stderr b/src/test/ui/attributes/attrs-with-no-formal-in-generics-1.stderr
index 55e7a987784..5b4f5222a2b 100644
--- a/src/test/ui/attributes/attrs-with-no-formal-in-generics-1.stderr
+++ b/src/test/ui/attributes/attrs-with-no-formal-in-generics-1.stderr
@@ -1,8 +1,8 @@
 error: trailing attribute after generic parameter
-  --> $DIR/attrs-with-no-formal-in-generics-1.rs:9:25
+  --> $DIR/attrs-with-no-formal-in-generics-1.rs:9:29
    |
-LL | impl<#[rustc_1] 'a, 'b, #[oops]> RefIntPair<'a, 'b> {
-   |                         ^^^^^^^ attributes must go before parameters
+LL | impl<#[rustc_dummy] 'a, 'b, #[oops]> RefIntPair<'a, 'b> {
+   |                             ^^^^^^^ attributes must go before parameters
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/attributes/attrs-with-no-formal-in-generics-2.rs b/src/test/ui/attributes/attrs-with-no-formal-in-generics-2.rs
index c795612acf0..d1d04403526 100644
--- a/src/test/ui/attributes/attrs-with-no-formal-in-generics-2.rs
+++ b/src/test/ui/attributes/attrs-with-no-formal-in-generics-2.rs
@@ -6,7 +6,7 @@
 
 struct RefAny<'a, T>(&'a T);
 
-impl<#[rustc_1] 'a, #[rustc_2] T, #[oops]> RefAny<'a, T> {}
+impl<#[rustc_dummy] 'a, #[rustc_dummy] T, #[oops]> RefAny<'a, T> {}
 //~^ ERROR trailing attribute after generic parameter
 
 fn main() {}
diff --git a/src/test/ui/attributes/attrs-with-no-formal-in-generics-2.stderr b/src/test/ui/attributes/attrs-with-no-formal-in-generics-2.stderr
index acd0ae3678a..fce3ff7de78 100644
--- a/src/test/ui/attributes/attrs-with-no-formal-in-generics-2.stderr
+++ b/src/test/ui/attributes/attrs-with-no-formal-in-generics-2.stderr
@@ -1,8 +1,8 @@
 error: trailing attribute after generic parameter
-  --> $DIR/attrs-with-no-formal-in-generics-2.rs:9:35
+  --> $DIR/attrs-with-no-formal-in-generics-2.rs:9:43
    |
-LL | impl<#[rustc_1] 'a, #[rustc_2] T, #[oops]> RefAny<'a, T> {}
-   |                                   ^^^^^^^ attributes must go before parameters
+LL | impl<#[rustc_dummy] 'a, #[rustc_dummy] T, #[oops]> RefAny<'a, T> {}
+   |                                           ^^^^^^^ attributes must go before parameters
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/consts/min_const_fn/allow_const_fn_ptr_feature_gate.rs b/src/test/ui/consts/min_const_fn/allow_const_fn_ptr_feature_gate.rs
index 0395795ef7b..0f9d3729295 100644
--- a/src/test/ui/consts/min_const_fn/allow_const_fn_ptr_feature_gate.rs
+++ b/src/test/ui/consts/min_const_fn/allow_const_fn_ptr_feature_gate.rs
@@ -5,7 +5,7 @@ const fn error(_: fn()) {}
 
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_allow_const_fn_ptr]
-//~^ ERROR unless otherwise specified, attributes with the prefix `rustc_` are reserved
+//~^ ERROR internal implementation detail
 const fn compiles(_: fn()) {}
 
 fn main() {}
diff --git a/src/test/ui/consts/min_const_fn/allow_const_fn_ptr_feature_gate.stderr b/src/test/ui/consts/min_const_fn/allow_const_fn_ptr_feature_gate.stderr
index c934307e918..d2ca0c8bc38 100644
--- a/src/test/ui/consts/min_const_fn/allow_const_fn_ptr_feature_gate.stderr
+++ b/src/test/ui/consts/min_const_fn/allow_const_fn_ptr_feature_gate.stderr
@@ -1,8 +1,8 @@
-error[E0658]: unless otherwise specified, attributes with the prefix `rustc_` are reserved for internal compiler diagnostics
-  --> $DIR/allow_const_fn_ptr_feature_gate.rs:7:3
+error[E0658]: internal implementation detail
+  --> $DIR/allow_const_fn_ptr_feature_gate.rs:7:1
    |
 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
diff --git a/src/test/ui/feature-gates/feature-gate-rustc-attrs.rs b/src/test/ui/feature-gates/feature-gate-rustc-attrs.rs
index 5ec413cc71d..d3a2e486416 100644
--- a/src/test/ui/feature-gates/feature-gate-rustc-attrs.rs
+++ b/src/test/ui/feature-gates/feature-gate-rustc-attrs.rs
@@ -1,6 +1,23 @@
 // Test that `#[rustc_*]` attributes are gated by `rustc_attrs` feature gate.
 
-#[rustc_foo]
-//~^ ERROR unless otherwise specified, attributes with the prefix `rustc_` are reserved
+#![feature(decl_macro)]
 
+mod rustc { pub macro unknown() {} }
+mod unknown { pub macro rustc() {} }
+
+#[rustc::unknown]
+//~^ ERROR attributes starting with `rustc` are reserved for use by the `rustc` compiler
+//~| ERROR macro `rustc::unknown` may not be used in attributes
+fn f() {}
+
+#[unknown::rustc]
+//~^ ERROR attributes starting with `rustc` are reserved for use by the `rustc` compiler
+//~| ERROR macro `unknown::rustc` may not be used in attributes
+fn g() {}
+
+#[rustc_dummy]
+//~^ ERROR used by the test suite
+#[rustc_unknown]
+//~^ ERROR attributes starting with `rustc` are reserved for use by the `rustc` compiler
+//~| ERROR attribute `rustc_unknown` is currently unknown
 fn main() {}
diff --git a/src/test/ui/feature-gates/feature-gate-rustc-attrs.stderr b/src/test/ui/feature-gates/feature-gate-rustc-attrs.stderr
index 3c823c8d4e2..cdc7b27a749 100644
--- a/src/test/ui/feature-gates/feature-gate-rustc-attrs.stderr
+++ b/src/test/ui/feature-gates/feature-gate-rustc-attrs.stderr
@@ -1,12 +1,60 @@
-error[E0658]: unless otherwise specified, attributes with the prefix `rustc_` are reserved for internal compiler diagnostics
-  --> $DIR/feature-gate-rustc-attrs.rs:3:3
+error[E0658]: attributes starting with `rustc` are reserved for use by the `rustc` compiler
+  --> $DIR/feature-gate-rustc-attrs.rs:8:3
    |
-LL | #[rustc_foo]
-   |   ^^^^^^^^^
+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: aborting due to previous error
+error: macro `rustc::unknown` may not be used in attributes
+  --> $DIR/feature-gate-rustc-attrs.rs:8:1
+   |
+LL | #[rustc::unknown]
+   | ^^^^^^^^^^^^^^^^^
+
+error[E0658]: attributes starting with `rustc` are reserved for use by the `rustc` compiler
+  --> $DIR/feature-gate-rustc-attrs.rs:13:12
+   |
+LL | #[unknown::rustc]
+   |            ^^^^^
+   |
+   = 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: macro `unknown::rustc` may not be used in attributes
+  --> $DIR/feature-gate-rustc-attrs.rs:13:1
+   |
+LL | #[unknown::rustc]
+   | ^^^^^^^^^^^^^^^^^
+
+error[E0658]: attributes starting with `rustc` are reserved for use by the `rustc` compiler
+  --> $DIR/feature-gate-rustc-attrs.rs:20:3
+   |
+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
+  --> $DIR/feature-gate-rustc-attrs.rs:20:3
+   |
+LL | #[rustc_unknown]
+   |   ^^^^^^^^^^^^^
+   |
+   = 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]: used by the test suite
+  --> $DIR/feature-gate-rustc-attrs.rs:18:1
+   |
+LL | #[rustc_dummy]
+   | ^^^^^^^^^^^^^^
+   |
+   = 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: aborting due to 7 previous errors
 
 For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/generic/generic-param-attrs.rs b/src/test/ui/generic/generic-param-attrs.rs
index 39a600339aa..3c5cc84c6a6 100644
--- a/src/test/ui/generic/generic-param-attrs.rs
+++ b/src/test/ui/generic/generic-param-attrs.rs
@@ -1,44 +1,38 @@
 // This test previously ensured that attributes on formals in generic parameter
 // lists are rejected without a feature gate.
-//
-// (We are prefixing all tested features with `rustc_`, to ensure that
-// the attributes themselves won't be rejected by the compiler when
-// using `rustc_attrs` feature. There is a separate compile-fail/ test
-// ensuring that the attribute feature-gating works in this context.)
 
 // build-pass (FIXME(62277): could be check-pass?)
 
 #![feature(rustc_attrs)]
-#![allow(dead_code)]
-
-struct StLt<#[rustc_lt_struct] 'a>(&'a u32);
-struct StTy<#[rustc_ty_struct] I>(I);
-enum EnLt<#[rustc_lt_enum] 'b> { A(&'b u32), B }
-enum EnTy<#[rustc_ty_enum] J> { A(J), B }
-trait TrLt<#[rustc_lt_trait] 'c> { fn foo(&self, _: &'c [u32]) -> &'c u32; }
-trait TrTy<#[rustc_ty_trait] K> { fn foo(&self, _: K); }
-type TyLt<#[rustc_lt_type] 'd> = &'d u32;
-type TyTy<#[rustc_ty_type] L> = (L, );
-
-impl<#[rustc_lt_inherent] 'e> StLt<'e> { }
-impl<#[rustc_ty_inherent] M> StTy<M> { }
-impl<#[rustc_lt_impl_for] 'f> TrLt<'f> for StLt<'f> {
+
+struct StLt<#[rustc_dummy] 'a>(&'a u32);
+struct StTy<#[rustc_dummy] I>(I);
+enum EnLt<#[rustc_dummy] 'b> { A(&'b u32), B }
+enum EnTy<#[rustc_dummy] J> { A(J), B }
+trait TrLt<#[rustc_dummy] 'c> { fn foo(&self, _: &'c [u32]) -> &'c u32; }
+trait TrTy<#[rustc_dummy] K> { fn foo(&self, _: K); }
+type TyLt<#[rustc_dummy] 'd> = &'d u32;
+type TyTy<#[rustc_dummy] L> = (L, );
+
+impl<#[rustc_dummy] 'e> StLt<'e> { }
+impl<#[rustc_dummy] M> StTy<M> { }
+impl<#[rustc_dummy] 'f> TrLt<'f> for StLt<'f> {
     fn foo(&self, _: &'f [u32]) -> &'f u32 { loop { } }
 }
-impl<#[rustc_ty_impl_for] N> TrTy<N> for StTy<N> {
+impl<#[rustc_dummy] N> TrTy<N> for StTy<N> {
     fn foo(&self, _: N) { }
 }
 
-fn f_lt<#[rustc_lt_fn] 'g>(_: &'g [u32]) -> &'g u32 { loop { } }
-fn f_ty<#[rustc_ty_fn] O>(_: O) { }
+fn f_lt<#[rustc_dummy] 'g>(_: &'g [u32]) -> &'g u32 { loop { } }
+fn f_ty<#[rustc_dummy] O>(_: O) { }
 
 impl<I> StTy<I> {
-    fn m_lt<#[rustc_lt_meth] 'h>(_: &'h [u32]) -> &'h u32 { loop { } }
-    fn m_ty<#[rustc_ty_meth] P>(_: P) { }
+    fn m_lt<#[rustc_dummy] 'h>(_: &'h [u32]) -> &'h u32 { loop { } }
+    fn m_ty<#[rustc_dummy] P>(_: P) { }
 }
 
 fn hof_lt<Q>(_: Q)
-    where Q: for <#[rustc_lt_hof] 'i> Fn(&'i [u32]) -> &'i u32
+    where Q: for <#[rustc_dummy] 'i> Fn(&'i [u32]) -> &'i u32
 {}
 
 fn main() {}
diff --git a/src/test/ui/nll/ty-outlives/projection-implied-bounds.rs b/src/test/ui/nll/ty-outlives/projection-implied-bounds.rs
index 1245ce8583e..fb50dce1af6 100644
--- a/src/test/ui/nll/ty-outlives/projection-implied-bounds.rs
+++ b/src/test/ui/nll/ty-outlives/projection-implied-bounds.rs
@@ -1,10 +1,7 @@
-// compile-flags:-Zborrowck=mir -Zverbose
-
 // Test that we can deduce when projections like `T::Item` outlive the
 // function body. Test that this does not imply that `T: 'a` holds.
 
-#![allow(warnings)]
-#![feature(rustc_attrs)]
+// compile-flags:-Zborrowck=mir -Zverbose
 
 use std::cell::Cell;
 
@@ -18,7 +15,6 @@ where
     f(&value, Cell::new(&n));
 }
 
-#[rustc_errors]
 fn generic1<T: Iterator>(value: T) {
     // No error here:
     twice(value, |value_ref, item| invoke1(item));
@@ -30,7 +26,6 @@ where
 {
 }
 
-#[rustc_errors]
 fn generic2<T: Iterator>(value: T) {
     twice(value, |value_ref, item| invoke2(value_ref, item));
     //~^ ERROR the parameter type `T` may not live long enough
diff --git a/src/test/ui/nll/ty-outlives/projection-implied-bounds.stderr b/src/test/ui/nll/ty-outlives/projection-implied-bounds.stderr
index 9cdb78a1028..9f0c60c1e17 100644
--- a/src/test/ui/nll/ty-outlives/projection-implied-bounds.stderr
+++ b/src/test/ui/nll/ty-outlives/projection-implied-bounds.stderr
@@ -1,5 +1,5 @@
 error[E0310]: the parameter type `T` may not live long enough
-  --> $DIR/projection-implied-bounds.rs:35:18
+  --> $DIR/projection-implied-bounds.rs:30:18
    |
 LL |     twice(value, |value_ref, item| invoke2(value_ref, item));
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/src/test/ui/nll/ty-outlives/ty-param-implied-bounds.rs b/src/test/ui/nll/ty-outlives/ty-param-implied-bounds.rs
index 27c3e89c1c3..a68c3cf12fd 100644
--- a/src/test/ui/nll/ty-outlives/ty-param-implied-bounds.rs
+++ b/src/test/ui/nll/ty-outlives/ty-param-implied-bounds.rs
@@ -4,9 +4,6 @@
 // Test that we assume that universal types like `T` outlive the
 // function body.
 
-#![allow(warnings)]
-#![feature(rustc_attrs)]
-
 use std::cell::Cell;
 
 fn twice<F, T>(value: T, mut f: F)
@@ -17,7 +14,6 @@ where
     f(Cell::new(&value));
 }
 
-#[rustc_errors]
 fn generic<T>(value: T) {
     // No error here:
     twice(value, |r| invoke(r));
diff --git a/src/test/ui/object-lifetime/object-lifetime-default.stderr b/src/test/ui/object-lifetime/object-lifetime-default.stderr
index 2642cdff2bf..f71c8cd0e0c 100644
--- a/src/test/ui/object-lifetime/object-lifetime-default.stderr
+++ b/src/test/ui/object-lifetime/object-lifetime-default.stderr
@@ -1,20 +1,20 @@
-error: 'a,Ambiguous
-  --> $DIR/object-lifetime-default.rs:24:1
+error: BaseDefault
+  --> $DIR/object-lifetime-default.rs:6:1
    |
-LL | struct G<'a,'b,T:'a,U:'a+'b>(&'a T, &'b U);
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | struct A<T>(T);
+   | ^^^^^^^^^^^^^^^
 
-error: 'a,'b
-  --> $DIR/object-lifetime-default.rs:21:1
+error: BaseDefault
+  --> $DIR/object-lifetime-default.rs:9:1
    |
-LL | struct F<'a,'b,T:'a,U:'b>(&'a T, &'b U);
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | struct B<'a,T>(&'a (), T);
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: 'b
-  --> $DIR/object-lifetime-default.rs:18:1
+error: 'a
+  --> $DIR/object-lifetime-default.rs:12:1
    |
-LL | struct E<'a,'b:'a,T:'b>(&'a T, &'b T);
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | struct C<'a,T:'a>(&'a T);
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: Ambiguous
   --> $DIR/object-lifetime-default.rs:15:1
@@ -22,23 +22,23 @@ error: Ambiguous
 LL | struct D<'a,'b,T:'a+'b>(&'a T, &'b T);
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: 'a
-  --> $DIR/object-lifetime-default.rs:12:1
+error: 'b
+  --> $DIR/object-lifetime-default.rs:18:1
    |
-LL | struct C<'a,T:'a>(&'a T);
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | struct E<'a,'b:'a,T:'b>(&'a T, &'b T);
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: BaseDefault
-  --> $DIR/object-lifetime-default.rs:9:1
+error: 'a,'b
+  --> $DIR/object-lifetime-default.rs:21:1
    |
-LL | struct B<'a,T>(&'a (), T);
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | struct F<'a,'b,T:'a,U:'b>(&'a T, &'b U);
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: BaseDefault
-  --> $DIR/object-lifetime-default.rs:6:1
+error: 'a,Ambiguous
+  --> $DIR/object-lifetime-default.rs:24:1
    |
-LL | struct A<T>(T);
-   | ^^^^^^^^^^^^^^^
+LL | struct G<'a,'b,T:'a,U:'a+'b>(&'a T, &'b U);
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: aborting due to 7 previous errors
 
diff --git a/src/test/ui/proc-macro/expand-to-unstable-2.rs b/src/test/ui/proc-macro/expand-to-unstable-2.rs
index 4b4ba52ecd7..437ae930934 100644
--- a/src/test/ui/proc-macro/expand-to-unstable-2.rs
+++ b/src/test/ui/proc-macro/expand-to-unstable-2.rs
@@ -1,12 +1,12 @@
 // aux-build:derive-unstable-2.rs
 
-#![allow(warnings)]
-
 #[macro_use]
 extern crate derive_unstable_2;
 
 #[derive(Unstable)]
-//~^ ERROR: reserved for internal compiler
+//~^ ERROR attributes starting with `rustc` are reserved for use by the `rustc` compiler
+//~| ERROR attribute `rustc_foo` is currently unknown to the compiler
+
 struct A;
 
 fn main() {
diff --git a/src/test/ui/proc-macro/expand-to-unstable-2.stderr b/src/test/ui/proc-macro/expand-to-unstable-2.stderr
index e2f51dd3d5d..803773db88e 100644
--- a/src/test/ui/proc-macro/expand-to-unstable-2.stderr
+++ b/src/test/ui/proc-macro/expand-to-unstable-2.stderr
@@ -1,5 +1,5 @@
-error[E0658]: unless otherwise specified, attributes with the prefix `rustc_` are reserved for internal compiler diagnostics
-  --> $DIR/expand-to-unstable-2.rs:8:10
+error[E0658]: attributes starting with `rustc` are reserved for use by the `rustc` compiler
+  --> $DIR/expand-to-unstable-2.rs:6:10
    |
 LL | #[derive(Unstable)]
    |          ^^^^^^^^
@@ -7,6 +7,15 @@ 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: aborting due to previous error
+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)]
+   |          ^^^^^^^^
+   |
+   = note: for more information, see https://github.com/rust-lang/rust/issues/29642
+   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/reserved/reserved-attr-on-macro.rs b/src/test/ui/reserved/reserved-attr-on-macro.rs
index 96c63ba4db8..cb535362266 100644
--- a/src/test/ui/reserved/reserved-attr-on-macro.rs
+++ b/src/test/ui/reserved/reserved-attr-on-macro.rs
@@ -1,5 +1,7 @@
 #[rustc_attribute_should_be_reserved]
-//~^ ERROR unless otherwise specified, attributes with the prefix `rustc_` are reserved
+//~^ ERROR attribute `rustc_attribute_should_be_reserved` is currently unknown
+//~| ERROR attributes starting with `rustc` are reserved for use by the `rustc` compiler
+
 macro_rules! foo {
     () => (());
 }
diff --git a/src/test/ui/reserved/reserved-attr-on-macro.stderr b/src/test/ui/reserved/reserved-attr-on-macro.stderr
index c8738d1ed34..0c62c82017e 100644
--- a/src/test/ui/reserved/reserved-attr-on-macro.stderr
+++ b/src/test/ui/reserved/reserved-attr-on-macro.stderr
@@ -1,4 +1,4 @@
-error[E0658]: unless otherwise specified, attributes with the prefix `rustc_` are reserved for internal compiler diagnostics
+error[E0658]: attributes starting with `rustc` are reserved for use by the `rustc` compiler
   --> $DIR/reserved-attr-on-macro.rs:1:3
    |
 LL | #[rustc_attribute_should_be_reserved]
@@ -7,14 +7,23 @@ 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
+  --> $DIR/reserved-attr-on-macro.rs:1:3
+   |
+LL | #[rustc_attribute_should_be_reserved]
+   |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: for more information, see https://github.com/rust-lang/rust/issues/29642
+   = help: add #![feature(custom_attribute)] to the crate attributes to enable
+
 error: cannot determine resolution for the macro `foo`
-  --> $DIR/reserved-attr-on-macro.rs:8:5
+  --> $DIR/reserved-attr-on-macro.rs:10:5
    |
 LL |     foo!();
    |     ^^^
    |
    = note: import resolution is stuck, try simplifying macro imports
 
-error: aborting due to 2 previous errors
+error: aborting due to 3 previous errors
 
 For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/suggestions/attribute-typos.rs b/src/test/ui/suggestions/attribute-typos.rs
index 13c6308b97e..0e10131ce8d 100644
--- a/src/test/ui/suggestions/attribute-typos.rs
+++ b/src/test/ui/suggestions/attribute-typos.rs
@@ -1,13 +1,11 @@
-#[deprcated]    //~ ERROR E0658
-fn foo() {}     //~| HELP a built-in attribute with a similar name exists
-                //~| SUGGESTION deprecated
-                //~| HELP add #![feature(custom_attribute)] to the crate attributes to enable
+#[deprcated] //~ ERROR attribute `deprcated` is currently unknown
+fn foo() {}
 
-#[tests]        //~ ERROR E0658
-fn bar() {}     //~| HELP a built-in attribute with a similar name exists
-                //~| SUGGESTION test
-                //~| HELP add #![feature(custom_attribute)] to the crate attributes to enable
+#[tests] //~ ERROR attribute `tests` is currently unknown to the compiler
+fn bar() {}
 
-#[rustc_err]    //~ ERROR E0658
-fn main() {}    //~| HELP add #![feature(rustc_attrs)] to the crate attributes to enable
-                // don't suggest rustc attributes
+#[rustc_err]
+//~^ ERROR attribute `rustc_err` is currently unknown
+//~| ERROR attributes starting with `rustc` are reserved for use by the `rustc` compiler
+
+fn main() {}
diff --git a/src/test/ui/suggestions/attribute-typos.stderr b/src/test/ui/suggestions/attribute-typos.stderr
index 8367ff20aa4..958688b4d39 100644
--- a/src/test/ui/suggestions/attribute-typos.stderr
+++ b/src/test/ui/suggestions/attribute-typos.stderr
@@ -1,5 +1,5 @@
-error[E0658]: unless otherwise specified, attributes with the prefix `rustc_` are reserved for internal compiler diagnostics
-  --> $DIR/attribute-typos.rs:11:3
+error[E0658]: attributes starting with `rustc` are reserved for use by the `rustc` compiler
+  --> $DIR/attribute-typos.rs:7:3
    |
 LL | #[rustc_err]
    |   ^^^^^^^^^
@@ -7,8 +7,17 @@ LL | #[rustc_err]
    = 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_err` is currently unknown to the compiler and may have meaning added to it in the future
+  --> $DIR/attribute-typos.rs:7:3
+   |
+LL | #[rustc_err]
+   |   ^^^^^^^^^
+   |
+   = 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 `tests` is currently unknown to the compiler and may have meaning added to it in the future
-  --> $DIR/attribute-typos.rs:6:3
+  --> $DIR/attribute-typos.rs:4:3
    |
 LL | #[tests]
    |   ^^^^^ help: a built-in attribute with a similar name exists: `test`
@@ -25,6 +34,6 @@ LL | #[deprcated]
    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
    = help: add #![feature(custom_attribute)] to the crate attributes to enable
 
-error: aborting due to 3 previous errors
+error: aborting due to 4 previous errors
 
 For more information about this error, try `rustc --explain E0658`.