introduce `negative_impls` feature gate and document

They used to be covered by `optin_builtin_traits` but negative impls
are now applicable to all traits, not just auto traits.

This also adds docs in the unstable book for the current state of auto traits.

6 files changed, 6 insertions, 5 deletions

diff --git a/src/test/rustdoc/empty-section.rs b/src/test/rustdoc/empty-section.rs
index d95f3a80365..665aa38b11e 100644
--- a/src/test/rustdoc/empty-section.rs
+++ b/src/test/rustdoc/empty-section.rs
@@ -1,6 +1,6 @@
 #![crate_name = "foo"]
 
-#![feature(optin_builtin_traits)]
+#![feature(negative_impls)]
 
 pub struct Foo;
 
diff --git a/src/test/rustdoc/impl-parts-crosscrate.rs b/src/test/rustdoc/impl-parts-crosscrate.rs
index f9583d1a722..a68db9c70ad 100644
--- a/src/test/rustdoc/impl-parts-crosscrate.rs
+++ b/src/test/rustdoc/impl-parts-crosscrate.rs
@@ -1,7 +1,7 @@
 // aux-build:rustdoc-impl-parts-crosscrate.rs
 // ignore-cross-compile
 
-#![feature(optin_builtin_traits)]
+#![feature(negative_impls)]
 
 extern crate rustdoc_impl_parts_crosscrate;
 
diff --git a/src/test/rustdoc/impl-parts.rs b/src/test/rustdoc/impl-parts.rs
index fbb4e725481..68baca9a04e 100644
--- a/src/test/rustdoc/impl-parts.rs
+++ b/src/test/rustdoc/impl-parts.rs
@@ -1,3 +1,4 @@
+#![feature(negative_impls)]
 #![feature(optin_builtin_traits)]
 
 pub auto trait AnOibit {}
diff --git a/src/test/rustdoc/issue-55321.rs b/src/test/rustdoc/issue-55321.rs
index 257cb32c65c..8c001db06c5 100644
--- a/src/test/rustdoc/issue-55321.rs
+++ b/src/test/rustdoc/issue-55321.rs
@@ -1,4 +1,4 @@
-#![feature(optin_builtin_traits)]
+#![feature(negative_impls)]
 
 // @has issue_55321/struct.A.html
 // @has - '//*[@id="implementations-list"]/*[@class="impl"]//code' "impl !Send for A"
diff --git a/src/test/rustdoc/negative-impl-sidebar.rs b/src/test/rustdoc/negative-impl-sidebar.rs
index 838ca0402e4..cb46d1778d9 100644
--- a/src/test/rustdoc/negative-impl-sidebar.rs
+++ b/src/test/rustdoc/negative-impl-sidebar.rs
@@ -1,4 +1,4 @@
-#![feature(optin_builtin_traits)]
+#![feature(negative_impls)]
 #![crate_name = "foo"]
 
 pub struct Foo;
diff --git a/src/test/rustdoc/negative-impl.rs b/src/test/rustdoc/negative-impl.rs
index 8ac87f4f0cb..d76aac6906c 100644
--- a/src/test/rustdoc/negative-impl.rs
+++ b/src/test/rustdoc/negative-impl.rs
@@ -1,4 +1,4 @@
-#![feature(optin_builtin_traits)]
+#![feature(negative_impls)]
 
 // @matches negative_impl/struct.Alpha.html '//pre' "pub struct Alpha"
 pub struct Alpha;