Auto merge of #68685 - Dylan-DPC:rollup-rkbo05z, r=Dylan-DPC

Rollup of 6 pull requests

Successful merges:

 - #68588 (check_unsafety: more code reuse)
 - #68638 (Add missing links for cmp traits)
 - #68660 (Fix typo.)
 - #68669 (suggest adding space in accidental doc comments)
 - #68670 (clarify "incorrect issue" error)
 - #68680 (Add `#![doc(html_playground_url = ...)]` to alloc crate)

Failed merges:

r? @ghost

src/test/ui/feature-gate/unstable-attribute-allow-issue-0.rs

@@ -9,5 +9,5 @@ fn unstable_issue_0() {}
 #[unstable(feature = "unstable_test_feature", issue = "none")]
 fn unstable_issue_none() {}
 
-#[unstable(feature = "unstable_test_feature", issue = "something")] //~ ERROR incorrect 'issue'
-fn unstable_issue_not_allowed() {}
+#[unstable(feature = "unstable_test_feature", issue = "something")]
+fn unstable_issue_not_allowed() {} //~^ ERROR `issue` must be a numeric string or "none"

src/test/ui/feature-gate/unstable-attribute-allow-issue-0.stderr

@@ -1,8 +1,10 @@
-error[E0545]: incorrect 'issue'
-  --> $DIR/unstable-attribute-allow-issue-0.rs:12:1
+error[E0545]: `issue` must be a numeric string or "none"
+  --> $DIR/unstable-attribute-allow-issue-0.rs:12:47
    |
 LL | #[unstable(feature = "unstable_test_feature", issue = "something")]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |                                               ^^^^^^^^-----------
+   |                                                       |
+   |                                                       invalid digit found in string
 
 error: aborting due to previous error
 

src/test/ui/parser/doc-comment-in-stmt.rs

@@ -0,0 +1,20 @@
+fn foo() -> bool {
+    false
+    //!self.allow_ty_infer()
+    //~^ ERROR found doc comment
+}
+
+fn bar() -> bool {
+    false
+    /*! bar */ //~ ERROR found doc comment
+}
+
+fn baz() -> i32 {
+    1 /** baz */ //~ ERROR found doc comment
+}
+
+fn quux() -> i32 {
+    2 /*! quux */ //~ ERROR found doc comment
+}
+
+fn main() {}

src/test/ui/parser/doc-comment-in-stmt.stderr

@@ -0,0 +1,50 @@
+error: expected one of `.`, `;`, `?`, `}`, or an operator, found doc comment `//!self.allow_ty_infer()`
+  --> $DIR/doc-comment-in-stmt.rs:3:5
+   |
+LL |     false
+   |          - expected one of `.`, `;`, `?`, `}`, or an operator
+LL |     //!self.allow_ty_infer()
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^ unexpected token
+   |
+help: add a space before `!` to use a regular comment
+   |
+LL |     // !self.allow_ty_infer()
+   |     ^^^^
+
+error: expected one of `.`, `;`, `?`, `}`, or an operator, found doc comment `/*! bar */`
+  --> $DIR/doc-comment-in-stmt.rs:9:5
+   |
+LL |     false
+   |          - expected one of `.`, `;`, `?`, `}`, or an operator
+LL |     /*! bar */
+   |     ^^^^^^^^^^ unexpected token
+   |
+help: add a space before `!` to use a regular comment
+   |
+LL |     /* ! bar */
+   |     ^^^^
+
+error: expected one of `.`, `;`, `?`, `}`, or an operator, found doc comment `/** baz */`
+  --> $DIR/doc-comment-in-stmt.rs:13:7
+   |
+LL |     1 /** baz */
+   |       ^^^^^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
+   |
+help: add a space before `*` to use a regular comment
+   |
+LL |     1 /* * baz */
+   |       ^^^^
+
+error: expected one of `.`, `;`, `?`, `}`, or an operator, found doc comment `/*! quux */`
+  --> $DIR/doc-comment-in-stmt.rs:17:7
+   |
+LL |     2 /*! quux */
+   |       ^^^^^^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
+   |
+help: add a space before `!` to use a regular comment
+   |
+LL |     2 /* ! quux */
+   |       ^^^^
+
+error: aborting due to 4 previous errors
+

src/test/ui/stability-attribute/stability-attribute-sanity-2.rs

@@ -10,7 +10,7 @@ fn f1() { }
 #[stable(feature = "a", sinse = "1.0.0")] //~ ERROR unknown meta item 'sinse'
 fn f2() { }
 
-#[unstable(feature = "a", issue = "no")] //~ ERROR incorrect 'issue'
+#[unstable(feature = "a", issue = "no")] //~ ERROR `issue` must be a numeric string or "none"
 fn f3() { }
 
 fn main() { }

src/test/ui/stability-attribute/stability-attribute-sanity-2.stderr

@@ -10,11 +10,13 @@ error[E0541]: unknown meta item 'sinse'
 LL | #[stable(feature = "a", sinse = "1.0.0")]
    |                         ^^^^^^^^^^^^^^^ expected one of `since`, `note`
 
-error[E0545]: incorrect 'issue'
-  --> $DIR/stability-attribute-sanity-2.rs:13:1
+error[E0545]: `issue` must be a numeric string or "none"
+  --> $DIR/stability-attribute-sanity-2.rs:13:27
    |
 LL | #[unstable(feature = "a", issue = "no")]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |                           ^^^^^^^^----
+   |                                   |
+   |                                   invalid digit found in string
 
 error: aborting due to 3 previous errors