Rollup merge of #64675 - Centril:deprecate-plugin, r=oli-obk

Deprecate `#![plugin]` & `#[plugin_registrar]`

This PR deprecates `#![plugin]` and `#[plugin_registrar]`.

~A removal deadline is set: 1.44.0. This will be in 9 months from now and should give everyone who is still relying on the feature ample time to rid themselves of this dependency.~

cc https://github.com/rust-lang/rust/issues/29597

r? @Mark-Simulacrum

src/libsyntax/feature_gate/builtin_attrs.rs

@@ -278,10 +278,23 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
     ),
 
     // Plugins:
-    ungated!(plugin_registrar, Normal, template!(Word)),
-    gated!(
-        plugin, CrateLevel, template!(List: "name|name(args)"),
-        "compiler plugins are experimental and possibly buggy",
+    (
+        sym::plugin_registrar, Normal, template!(Word),
+        Gated(
+            Stability::Deprecated("https://github.com/rust-lang/rust/issues/29597", None),
+            sym::plugin_registrar,
+            "compiler plugins are deprecated",
+            cfg_fn!(plugin_registrar)
+        )
+    ),
+    (
+        sym::plugin, CrateLevel, template!(List: "name|name(args)"),
+        Gated(
+            Stability::Deprecated("https://github.com/rust-lang/rust/issues/29597", None),
+            sym::plugin,
+            "compiler plugins are deprecated",
+            cfg_fn!(plugin)
+        )
     ),
 
     // Testing:

src/test/run-make-fulldeps/hotplug_codegen_backend/the_backend.rs

@@ -41,7 +41,7 @@ impl MetadataLoader for NoLlvmMetadataLoader {
 struct TheBackend;
 
 impl CodegenBackend for TheBackend {
-    fn metadata_loader(&self) -> Box<MetadataLoader + Sync> {
+    fn metadata_loader(&self) -> Box<dyn MetadataLoader + Sync> {
         Box::new(NoLlvmMetadataLoader)
     }
 
@@ -64,7 +64,7 @@ impl CodegenBackend for TheBackend {
         tcx: TyCtxt<'tcx>,
         _metadata: EncodedMetadata,
         _need_metadata_module: bool,
-    ) -> Box<Any> {
+    ) -> Box<dyn Any> {
         use rustc::hir::def_id::LOCAL_CRATE;
 
         Box::new(tcx.crate_name(LOCAL_CRATE) as Symbol)
@@ -72,7 +72,7 @@ impl CodegenBackend for TheBackend {
 
     fn join_codegen_and_link(
         &self,
-        ongoing_codegen: Box<Any>,
+        ongoing_codegen: Box<dyn Any>,
         sess: &Session,
         _dep_graph: &DepGraph,
         outputs: &OutputFilenames,
@@ -97,6 +97,6 @@ impl CodegenBackend for TheBackend {
 
 /// This is the entrypoint for a hot plugged rustc_codegen_llvm
 #[no_mangle]
-pub fn __rustc_codegen_backend() -> Box<CodegenBackend> {
+pub fn __rustc_codegen_backend() -> Box<dyn CodegenBackend> {
     Box::new(TheBackend)
 }

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

@@ -1,6 +1,7 @@
 // aux-build:attr-plugin-test.rs
 
 #![plugin(attr_plugin_test)]
-//~^ ERROR compiler plugins are experimental and possibly buggy
+//~^ ERROR compiler plugins are deprecated
+//~| WARN use of deprecated attribute `plugin`: compiler plugins are deprecated
 
 fn main() {}

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

@@ -1,4 +1,4 @@
-error[E0658]: compiler plugins are experimental and possibly buggy
+error[E0658]: compiler plugins are deprecated
   --> $DIR/gated-plugin.rs:3:1
    |
 LL | #![plugin(attr_plugin_test)]
@@ -7,6 +7,14 @@ 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
 
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/gated-plugin.rs:3:1
+   |
+LL | #![plugin(attr_plugin_test)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 error: aborting due to previous error
 
 For more information about this error, try `rustc --explain E0658`.

src/test/ui-fulldeps/issue-15778-fail.rs

@@ -4,5 +4,6 @@
 
 #![feature(plugin)] //~ ERROR crate is not marked with #![crate_okay]
 #![plugin(lint_for_crate)]
+//~^ WARN use of deprecated attribute `plugin`
 
 pub fn main() { }

src/test/ui-fulldeps/issue-15778-fail.stderr

@@ -1,9 +1,18 @@
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/issue-15778-fail.rs:6:1
+   |
+LL | #![plugin(lint_for_crate)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 error: crate is not marked with #![crate_okay]
   --> $DIR/issue-15778-fail.rs:5:1
    |
 LL | / #![feature(plugin)]
 LL | | #![plugin(lint_for_crate)]
 LL | |
+LL | |
 LL | | pub fn main() { }
    | |_________________^
    |

src/test/ui-fulldeps/issue-15778-pass.stderr

@@ -0,0 +1,8 @@
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/issue-15778-pass.rs:8:1
+   |
+LL | #![plugin(lint_for_crate_rpass)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+

src/test/ui-fulldeps/issue-40001.stderr

@@ -0,0 +1,8 @@
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/issue-40001.rs:6:1
+   |
+LL | #![plugin(issue_40001_plugin)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+

src/test/ui-fulldeps/lint-group-plugin-deny-cmdline.rs

@@ -3,7 +3,9 @@
 // compile-flags: -D lint-me
 
 #![feature(plugin)]
+
 #![plugin(lint_group_plugin_test)]
+//~^ WARN use of deprecated attribute `plugin`
 
 fn lintme() { } //~ ERROR item is named 'lintme'
 

src/test/ui-fulldeps/lint-group-plugin-deny-cmdline.stderr

@@ -1,5 +1,13 @@
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/lint-group-plugin-deny-cmdline.rs:7:1
+   |
+LL | #![plugin(lint_group_plugin_test)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 error: item is named 'lintme'
-  --> $DIR/lint-group-plugin-deny-cmdline.rs:8:1
+  --> $DIR/lint-group-plugin-deny-cmdline.rs:10:1
    |
 LL | fn lintme() { }
    | ^^^^^^^^^^^^^^^
@@ -7,7 +15,7 @@ LL | fn lintme() { }
    = note: `-D test-lint` implied by `-D lint-me`
 
 error: item is named 'pleaselintme'
-  --> $DIR/lint-group-plugin-deny-cmdline.rs:10:1
+  --> $DIR/lint-group-plugin-deny-cmdline.rs:12:1
    |
 LL | fn pleaselintme() { }
    | ^^^^^^^^^^^^^^^^^^^^^

src/test/ui-fulldeps/lint-group-plugin.stderr

@@ -1,3 +1,11 @@
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/lint-group-plugin.rs:6:1
+   |
+LL | #![plugin(lint_group_plugin_test)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 warning: item is named 'lintme'
   --> $DIR/lint-group-plugin.rs:9:1
    |

src/test/ui-fulldeps/lint-plugin-cmdline-allow.stderr

@@ -1,3 +1,11 @@
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/lint-plugin-cmdline-allow.rs:8:1
+   |
+LL | #![plugin(lint_plugin_test)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 warning: function is never used: `lintme`
   --> $DIR/lint-plugin-cmdline-allow.rs:10:1
    |

src/test/ui-fulldeps/lint-plugin-deny-attr.rs

@@ -3,6 +3,7 @@
 
 #![feature(plugin)]
 #![plugin(lint_plugin_test)]
+//~^ WARN use of deprecated attribute `plugin`
 #![deny(test_lint)]
 
 fn lintme() { } //~ ERROR item is named 'lintme'

src/test/ui-fulldeps/lint-plugin-deny-attr.stderr

@@ -1,11 +1,19 @@
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/lint-plugin-deny-attr.rs:5:1
+   |
+LL | #![plugin(lint_plugin_test)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 error: item is named 'lintme'
-  --> $DIR/lint-plugin-deny-attr.rs:8:1
+  --> $DIR/lint-plugin-deny-attr.rs:9:1
    |
 LL | fn lintme() { }
    | ^^^^^^^^^^^^^^^
    |
 note: lint level defined here
-  --> $DIR/lint-plugin-deny-attr.rs:6:9
+  --> $DIR/lint-plugin-deny-attr.rs:7:9
    |
 LL | #![deny(test_lint)]
    |         ^^^^^^^^^

src/test/ui-fulldeps/lint-plugin-deny-cmdline.rs

@@ -4,6 +4,7 @@
 
 #![feature(plugin)]
 #![plugin(lint_plugin_test)]
+//~^ WARN use of deprecated attribute `plugin`
 
 fn lintme() { } //~ ERROR item is named 'lintme'
 

src/test/ui-fulldeps/lint-plugin-deny-cmdline.stderr

@@ -1,5 +1,13 @@
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/lint-plugin-deny-cmdline.rs:6:1
+   |
+LL | #![plugin(lint_plugin_test)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 error: item is named 'lintme'
-  --> $DIR/lint-plugin-deny-cmdline.rs:8:1
+  --> $DIR/lint-plugin-deny-cmdline.rs:9:1
    |
 LL | fn lintme() { }
    | ^^^^^^^^^^^^^^^

src/test/ui-fulldeps/lint-plugin-forbid-attrs.rs

@@ -3,6 +3,7 @@
 
 #![feature(plugin)]
 #![plugin(lint_plugin_test)]
+//~^ WARN use of deprecated attribute `plugin`
 #![forbid(test_lint)]
 
 fn lintme() { } //~ ERROR item is named 'lintme'

src/test/ui-fulldeps/lint-plugin-forbid-attrs.stderr

@@ -1,5 +1,5 @@
 error[E0453]: allow(test_lint) overruled by outer forbid(test_lint)
-  --> $DIR/lint-plugin-forbid-attrs.rs:10:9
+  --> $DIR/lint-plugin-forbid-attrs.rs:11:9
    |
 LL | #![forbid(test_lint)]
    |           --------- `forbid` level set here
@@ -7,14 +7,22 @@ LL | #![forbid(test_lint)]
 LL | #[allow(test_lint)]
    |         ^^^^^^^^^ overruled by previous forbid
 
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/lint-plugin-forbid-attrs.rs:5:1
+   |
+LL | #![plugin(lint_plugin_test)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 error: item is named 'lintme'
-  --> $DIR/lint-plugin-forbid-attrs.rs:8:1
+  --> $DIR/lint-plugin-forbid-attrs.rs:9:1
    |
 LL | fn lintme() { }
    | ^^^^^^^^^^^^^^^
    |
 note: lint level defined here
-  --> $DIR/lint-plugin-forbid-attrs.rs:6:11
+  --> $DIR/lint-plugin-forbid-attrs.rs:7:11
    |
 LL | #![forbid(test_lint)]
    |           ^^^^^^^^^

src/test/ui-fulldeps/lint-plugin-forbid-cmdline.rs

@@ -4,7 +4,7 @@
 
 #![feature(plugin)]
 #![plugin(lint_plugin_test)]
-
+//~^ WARN use of deprecated attribute `plugin`
 fn lintme() { } //~ ERROR item is named 'lintme'
 
 #[allow(test_lint)] //~ ERROR allow(test_lint) overruled by outer forbid(test_lint)

src/test/ui-fulldeps/lint-plugin-forbid-cmdline.stderr

@@ -6,6 +6,14 @@ LL | #[allow(test_lint)]
    |
    = note: `forbid` lint level was set on command line
 
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/lint-plugin-forbid-cmdline.rs:6:1
+   |
+LL | #![plugin(lint_plugin_test)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 error: item is named 'lintme'
   --> $DIR/lint-plugin-forbid-cmdline.rs:8:1
    |

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

@@ -1,3 +1,11 @@
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/lint-plugin.rs:5:1
+   |
+LL | #![plugin(lint_plugin_test)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 warning: item is named 'lintme'
   --> $DIR/lint-plugin.rs:8:1
    |

src/test/ui-fulldeps/lint-tool-cmdline-allow.stderr

@@ -2,6 +2,14 @@ warning: lint name `test_lint` is deprecated and does not have an effect anymore
    |
    = note: requested on the command line with `-A test_lint`
 
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/lint-tool-cmdline-allow.rs:8:1
+   |
+LL | #![plugin(lint_tool_test)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 warning: item is named 'lintme'
   --> $DIR/lint-tool-cmdline-allow.rs:10:1
    |

src/test/ui-fulldeps/lint-tool-test.rs

@@ -4,6 +4,7 @@
 
 #![feature(plugin)]
 #![plugin(lint_tool_test)]
+//~^ WARN use of deprecated attribute `plugin`
 #![allow(dead_code)]
 #![cfg_attr(foo, warn(test_lint))]
 //~^ WARNING lint name `test_lint` is deprecated and may not have an effect in the future

src/test/ui-fulldeps/lint-tool-test.stderr

@@ -1,5 +1,5 @@
 warning: lint name `test_lint` is deprecated and may not have an effect in the future. Also `cfg_attr(cargo-clippy)` won't be necessary anymore
-  --> $DIR/lint-tool-test.rs:8:23
+  --> $DIR/lint-tool-test.rs:9:23
    |
 LL | #![cfg_attr(foo, warn(test_lint))]
    |                       ^^^^^^^^^ help: change it to: `clippy::test_lint`
@@ -7,19 +7,19 @@ LL | #![cfg_attr(foo, warn(test_lint))]
    = note: `#[warn(renamed_and_removed_lints)]` on by default
 
 warning: lint name `clippy_group` is deprecated and may not have an effect in the future. Also `cfg_attr(cargo-clippy)` won't be necessary anymore
-  --> $DIR/lint-tool-test.rs:11:9
+  --> $DIR/lint-tool-test.rs:12:9
    |
 LL | #![deny(clippy_group)]
    |         ^^^^^^^^^^^^ help: change it to: `clippy::group`
 
 warning: lint name `test_group` is deprecated and may not have an effect in the future. Also `cfg_attr(cargo-clippy)` won't be necessary anymore
-  --> $DIR/lint-tool-test.rs:25:9
+  --> $DIR/lint-tool-test.rs:26:9
    |
 LL | #[allow(test_group)]
    |         ^^^^^^^^^^ help: change it to: `clippy::test_group`
 
 warning: unknown lint: `this_lint_does_not_exist`
-  --> $DIR/lint-tool-test.rs:27:8
+  --> $DIR/lint-tool-test.rs:28:8
    |
 LL | #[deny(this_lint_does_not_exist)]
    |        ^^^^^^^^^^^^^^^^^^^^^^^^
@@ -27,32 +27,40 @@ LL | #[deny(this_lint_does_not_exist)]
    = note: `#[warn(unknown_lints)]` on by default
 
 warning: lint name `test_lint` is deprecated and may not have an effect in the future. Also `cfg_attr(cargo-clippy)` won't be necessary anymore
-  --> $DIR/lint-tool-test.rs:8:23
+  --> $DIR/lint-tool-test.rs:9:23
    |
 LL | #![cfg_attr(foo, warn(test_lint))]
    |                       ^^^^^^^^^ help: change it to: `clippy::test_lint`
 
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/lint-tool-test.rs:6:1
+   |
+LL | #![plugin(lint_tool_test)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 error: item is named 'lintme'
-  --> $DIR/lint-tool-test.rs:14:1
+  --> $DIR/lint-tool-test.rs:15:1
    |
 LL | fn lintme() { }
    | ^^^^^^^^^^^^^^^
    |
 note: lint level defined here
-  --> $DIR/lint-tool-test.rs:11:9
+  --> $DIR/lint-tool-test.rs:12:9
    |
 LL | #![deny(clippy_group)]
    |         ^^^^^^^^^^^^
    = note: `#[deny(clippy::test_lint)]` implied by `#[deny(clippy::group)]`
 
 error: item is named 'lintmetoo'
-  --> $DIR/lint-tool-test.rs:22:5
+  --> $DIR/lint-tool-test.rs:23:5
    |
 LL |     fn lintmetoo() { }
    |     ^^^^^^^^^^^^^^^^^^
    |
 note: lint level defined here
-  --> $DIR/lint-tool-test.rs:11:9
+  --> $DIR/lint-tool-test.rs:12:9
    |
 LL | #![deny(clippy_group)]
    |         ^^^^^^^^^^^^

src/test/ui-fulldeps/llvm-pass-plugin.stderr

@@ -0,0 +1,8 @@
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/llvm-pass-plugin.rs:6:1
+   |
+LL | #![plugin(llvm_pass_plugin)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+

src/test/ui-fulldeps/lto-syntax-extension.stderr

@@ -0,0 +1,8 @@
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/lto-syntax-extension.rs:9:1
+   |
+LL | #![plugin(lto_syntax_extension_plugin)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+

src/test/ui-fulldeps/macro-crate-rlib.rs

@@ -5,5 +5,6 @@
 #![feature(plugin)]
 #![plugin(rlib_crate_test)]
 //~^ ERROR: plugin `rlib_crate_test` only found in rlib format, but must be available in dylib format
+//~| WARN use of deprecated attribute `plugin`: compiler plugins are deprecated
 
 fn main() {}

src/test/ui-fulldeps/macro-crate-rlib.stderr

@@ -4,5 +4,13 @@ error[E0457]: plugin `rlib_crate_test` only found in rlib format, but must be av
 LL | #![plugin(rlib_crate_test)]
    |           ^^^^^^^^^^^^^^^
 
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/macro-crate-rlib.rs:6:1
+   |
+LL | #![plugin(rlib_crate_test)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 error: aborting due to previous error
 

src/test/ui-fulldeps/outlive-expansion-phase.stderr

@@ -0,0 +1,8 @@
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/outlive-expansion-phase.rs:6:1
+   |
+LL | #![plugin(outlive_expansion_phase)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+

src/test/ui-fulldeps/plugin-args-1.stderr

@@ -0,0 +1,8 @@
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/plugin-args-1.rs:6:1
+   |
+LL | #![plugin(plugin_args)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+

src/test/ui-fulldeps/plugin-args-2.stderr

@@ -0,0 +1,8 @@
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/plugin-args-2.rs:6:1
+   |
+LL | #![plugin(plugin_args())]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+

src/test/ui-fulldeps/plugin-args-3.stderr

@@ -0,0 +1,8 @@
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/plugin-args-3.rs:6:1
+   |
+LL | #![plugin(plugin_args(hello(there), how(are="you")))]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+

src/test/ui-fulldeps/plugin-attr-register-deny.rs

@@ -3,6 +3,7 @@
 
 #![feature(plugin)]
 #![plugin(attr_plugin_test)]
+//~^ WARN use of deprecated attribute `plugin`
 #![deny(unused_attributes)]
 
 #[baz]

src/test/ui-fulldeps/plugin-attr-register-deny.stderr

@@ -1,23 +1,31 @@
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/plugin-attr-register-deny.rs:5:1
+   |
+LL | #![plugin(attr_plugin_test)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 error: unused attribute
-  --> $DIR/plugin-attr-register-deny.rs:14:5
+  --> $DIR/plugin-attr-register-deny.rs:15:5
    |
 LL |     #[bar]
    |     ^^^^^^
    |
 note: lint level defined here
-  --> $DIR/plugin-attr-register-deny.rs:6:9
+  --> $DIR/plugin-attr-register-deny.rs:7:9
    |
 LL | #![deny(unused_attributes)]
    |         ^^^^^^^^^^^^^^^^^
 
 error: crate-level attribute should be an inner attribute: add an exclamation mark: `#![foo]`
-  --> $DIR/plugin-attr-register-deny.rs:14:5
+  --> $DIR/plugin-attr-register-deny.rs:15:5
    |
 LL |     #[bar]
    |     ^^^^^^
 
 error: unused attribute
-  --> $DIR/plugin-attr-register-deny.rs:11:1
+  --> $DIR/plugin-attr-register-deny.rs:12:1
    |
 LL | #[foo]
    | ^^^^^^

src/test/ui-fulldeps/plugin-reexport.rs

@@ -4,6 +4,7 @@
 
 #![feature(plugin)]
 #![plugin(attr_plugin_test)]
+//~^ WARN use of deprecated attribute `plugin`
 
 pub use mac as reexport; //~ ERROR `mac` is private, and cannot be re-exported
 

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

@@ -1,15 +1,23 @@
 error[E0364]: `mac` is private, and cannot be re-exported
-  --> $DIR/plugin-reexport.rs:8:9
+  --> $DIR/plugin-reexport.rs:9:9
    |
 LL | pub use mac as reexport;
    |         ^^^^^^^^^^^^^^^
    |
 note: consider marking `mac` as `pub` in the imported module
-  --> $DIR/plugin-reexport.rs:8:9
+  --> $DIR/plugin-reexport.rs:9:9
    |
 LL | pub use mac as reexport;
    |         ^^^^^^^^^^^^^^^
 
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/plugin-reexport.rs:6:1
+   |
+LL | #![plugin(attr_plugin_test)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 error: aborting due to previous error
 
 For more information about this error, try `rustc --explain E0364`.

src/test/ui-fulldeps/roman-numerals-macro.stderr

@@ -0,0 +1,8 @@
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/roman-numerals-macro.rs:6:1
+   |
+LL | #![plugin(roman_numerals)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+

src/test/ui/feature-gate/issue-43106-gating-of-builtin-attrs.rs

@@ -32,9 +32,13 @@
 
 // check-pass
 
-#![feature(test)]
+#![feature(test, plugin_registrar)]
 #![warn(unused_attributes, unknown_lints)]
 
+// Exception, a gated and deprecated attribute.
+
+#![plugin_registrar] //~ WARN unused attribute
+
 // UNGATED WHITE-LISTED BUILT-IN ATTRIBUTES
 
 #![warn(x5400)] //~ WARN unknown lint: `x5400`
@@ -43,7 +47,6 @@
 #![deny(x5100)] //~ WARN unknown lint: `x5100`
 #![macro_use] // (allowed if no argument; see issue-43160-gating-of-macro_use.rs)
 #![macro_export] //~ WARN unused attribute
-#![plugin_registrar] //~ WARN unused attribute
 // skipping testing of cfg
 // skipping testing of cfg_attr
 #![main] //~ WARN unused attribute

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

@@ -1,6 +1,7 @@
 // Test that `#![plugin(...)]` attribute is gated by `plugin` feature gate
 
 #![plugin(foo)]
-//~^ ERROR compiler plugins are experimental and possibly buggy
+//~^ ERROR compiler plugins are deprecated
+//~| WARN use of deprecated attribute `plugin`: compiler plugins are deprecated
 
 fn main() {}

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

@@ -1,4 +1,4 @@
-error[E0658]: compiler plugins are experimental and possibly buggy
+error[E0658]: compiler plugins are deprecated
   --> $DIR/feature-gate-plugin.rs:3:1
    |
 LL | #![plugin(foo)]
@@ -7,6 +7,14 @@ LL | #![plugin(foo)]
    = note: for more information, see https://github.com/rust-lang/rust/issues/29597
    = help: add `#![feature(plugin)]` to the crate attributes to enable
 
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/feature-gate-plugin.rs:3:1
+   |
+LL | #![plugin(foo)]
+   | ^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 error: aborting due to previous error
 
 For more information about this error, try `rustc --explain E0658`.

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

@@ -3,6 +3,9 @@
 
 // the registration function isn't typechecked yet
 #[plugin_registrar]
+//~^ ERROR compiler plugins are deprecated
+//~| WARN use of deprecated attribute `plugin_registrar`: compiler plugins are deprecated
 pub fn registrar() {}
-//~^ ERROR compiler plugins are experimental
+//~^ ERROR compiler plugins are experimental and possibly buggy
+
 fn main() {}

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

@@ -1,5 +1,5 @@
 error[E0658]: compiler plugins are experimental and possibly buggy
-  --> $DIR/feature-gate-plugin_registrar.rs:6:1
+  --> $DIR/feature-gate-plugin_registrar.rs:8:1
    |
 LL | pub fn registrar() {}
    | ^^^^^^^^^^^^^^^^^^^^^
@@ -7,6 +7,23 @@ LL | pub fn registrar() {}
    = note: for more information, see https://github.com/rust-lang/rust/issues/29597
    = help: add `#![feature(plugin_registrar)]` to the crate attributes to enable
 
-error: aborting due to previous error
+error[E0658]: compiler plugins are deprecated
+  --> $DIR/feature-gate-plugin_registrar.rs:5:1
+   |
+LL | #[plugin_registrar]
+   | ^^^^^^^^^^^^^^^^^^^
+   |
+   = note: for more information, see https://github.com/rust-lang/rust/issues/29597
+   = help: add `#![feature(plugin_registrar)]` to the crate attributes to enable
+
+warning: use of deprecated attribute `plugin_registrar`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/feature-gate-plugin_registrar.rs:5:1
+   |
+LL | #[plugin_registrar]
+   | ^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0658`.

src/test/ui/invalid/invalid-plugin-attr.rs

@@ -3,5 +3,6 @@
 
 #[plugin(bla)]  //~ ERROR unused attribute
                 //~^ ERROR should be an inner attribute
+//~| WARN use of deprecated attribute `plugin`: compiler plugins are deprecated
 
 fn main() {}

src/test/ui/invalid/invalid-plugin-attr.stderr

@@ -1,3 +1,11 @@
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/invalid-plugin-attr.rs:4:1
+   |
+LL | #[plugin(bla)]
+   | ^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 error: unused attribute
   --> $DIR/invalid-plugin-attr.rs:4:1
    |

src/test/ui/malformed/malformed-plugin-1.rs

@@ -1,4 +1,5 @@
 #![feature(plugin)]
 #![plugin] //~ ERROR malformed `plugin` attribute
+//~| WARN use of deprecated attribute `plugin`: compiler plugins are deprecated
 
 fn main() {}

src/test/ui/malformed/malformed-plugin-1.stderr

@@ -4,5 +4,13 @@ error: malformed `plugin` attribute input
 LL | #![plugin]
    | ^^^^^^^^^^ help: must be of the form: `#[plugin(name|name(args))]`
 
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/malformed-plugin-1.rs:2:1
+   |
+LL | #![plugin]
+   | ^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 error: aborting due to previous error
 

src/test/ui/malformed/malformed-plugin-2.rs

@@ -1,4 +1,5 @@
 #![feature(plugin)]
 #![plugin="bleh"] //~ ERROR malformed `plugin` attribute
+//~| WARN use of deprecated attribute `plugin`: compiler plugins are deprecated
 
 fn main() {}

src/test/ui/malformed/malformed-plugin-2.stderr

@@ -4,5 +4,13 @@ error: malformed `plugin` attribute input
 LL | #![plugin="bleh"]
    | ^^^^^^^^^^^^^^^^^ help: must be of the form: `#[plugin(name|name(args))]`
 
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/malformed-plugin-2.rs:2:1
+   |
+LL | #![plugin="bleh"]
+   | ^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 error: aborting due to previous error
 

src/test/ui/malformed/malformed-plugin-3.rs

@@ -1,4 +1,5 @@
 #![feature(plugin)]
 #![plugin(foo="bleh")] //~ ERROR malformed `plugin` attribute
+//~| WARN use of deprecated attribute `plugin`: compiler plugins are deprecated
 
 fn main() {}

src/test/ui/malformed/malformed-plugin-3.stderr

@@ -4,5 +4,13 @@ error[E0498]: malformed `plugin` attribute
 LL | #![plugin(foo="bleh")]
    | ^^^^^^^^^^^^^^^^^^^^^^ malformed attribute
 
+warning: use of deprecated attribute `plugin`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/malformed-plugin-3.rs:2:1
+   |
+LL | #![plugin(foo="bleh")]
+   | ^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
 error: aborting due to previous error
 

src/test/ui/multiple-plugin-registrars.stderr

@@ -1,3 +1,17 @@
+warning: use of deprecated attribute `plugin_registrar`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/multiple-plugin-registrars.rs:6:1
+   |
+LL | #[plugin_registrar]
+   | ^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: `#[warn(deprecated)]` on by default
+
+warning: use of deprecated attribute `plugin_registrar`: compiler plugins are deprecated. See https://github.com/rust-lang/rust/issues/29597
+  --> $DIR/multiple-plugin-registrars.rs:9:1
+   |
+LL | #[plugin_registrar]
+   | ^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+
 error: multiple plugin registration functions found
    |
 note: one is here