Auto merge of #81271 - m-ou-se:rollup-xv7gq3w, r=m-ou-se

Rollup of 10 pull requests

Successful merges:

 - #80573 (Deny rustc::internal lints for rustdoc and clippy)
 - #81173 (Expand docs on Iterator::intersperse)
 - #81194 (Stabilize std::panic::panic_any.)
 - #81202 (Don't prefix 0x for each segments in `dbg!(Ipv6)`)
 - #81225 (Make 'docs' nullable in rustdoc-json output)
 - #81227 (Remove doctree::StructType)
 - #81233 (Document why not use concat! in dbg! macro)
 - #81236 (Gracefully handle loop labels missing leading `'` in different positions)
 - #81241 (Turn alloc's force_expr macro into a regular macro_rules.)
 - #81242 (Enforce statically that `MIN_NON_ZERO_CAP` is calculated at compile time)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

11 files changed, 338 insertions, 65 deletions

diff --git a/src/test/ui/issues/issue-1962.fixed b/src/test/ui/issues/issue-1962.fixed
index b810a90ef37..897fd172b29 100644
--- a/src/test/ui/issues/issue-1962.fixed
+++ b/src/test/ui/issues/issue-1962.fixed
@@ -3,8 +3,8 @@
 
 fn main() {
     let mut i = 0;
-    loop { //~ ERROR denote infinite loops with `loop
+    'a: loop { //~ ERROR denote infinite loops with `loop
         i += 1;
-        if i == 5 { break; }
+        if i == 5 { break 'a; }
     }
 }
diff --git a/src/test/ui/issues/issue-1962.rs b/src/test/ui/issues/issue-1962.rs
index 00d2bbd2850..71e87410087 100644
--- a/src/test/ui/issues/issue-1962.rs
+++ b/src/test/ui/issues/issue-1962.rs
@@ -3,8 +3,8 @@
 
 fn main() {
     let mut i = 0;
-    while true { //~ ERROR denote infinite loops with `loop
+    'a: while true { //~ ERROR denote infinite loops with `loop
         i += 1;
-        if i == 5 { break; }
+        if i == 5 { break 'a; }
     }
 }
diff --git a/src/test/ui/issues/issue-1962.stderr b/src/test/ui/issues/issue-1962.stderr
index 17142912696..4c32a4cf3dd 100644
--- a/src/test/ui/issues/issue-1962.stderr
+++ b/src/test/ui/issues/issue-1962.stderr
@@ -1,8 +1,8 @@
 error: denote infinite loops with `loop { ... }`
   --> $DIR/issue-1962.rs:6:5
    |
-LL |     while true {
-   |     ^^^^^^^^^^ help: use `loop`
+LL |     'a: while true {
+   |     ^^^^^^^^^^^^^^ help: use `loop`
    |
    = note: requested on the command line with `-D while-true`
 
diff --git a/src/test/ui/issues/issue-27042.stderr b/src/test/ui/issues/issue-27042.stderr
index 7dee1a6a5f0..59ef28481d0 100644
--- a/src/test/ui/issues/issue-27042.stderr
+++ b/src/test/ui/issues/issue-27042.stderr
@@ -4,7 +4,7 @@ warning: denote infinite loops with `loop { ... }`
 LL | /         'b:
 LL | |
 LL | |         while true { break }; // but here we cite the whole loop
-   | |____________________________^ help: use `loop`
+   | |__________________^ help: use `loop`
    |
    = note: `#[warn(while_true)]` on by default
 
diff --git a/src/test/ui/label/label_misspelled.rs b/src/test/ui/label/label_misspelled.rs
index ebfd5642c9f..e3180b06ecb 100644
--- a/src/test/ui/label/label_misspelled.rs
+++ b/src/test/ui/label/label_misspelled.rs
@@ -1,18 +1,62 @@
+#![warn(unused_labels)]
+
 fn main() {
+    'while_loop: while true { //~ WARN denote infinite loops with
+        //~^ WARN unused label
+        while_loop;
+        //~^ ERROR cannot find value `while_loop` in this scope
+    };
+    'while_let: while let Some(_) = Some(()) {
+        //~^ WARN unused label
+        while_let;
+        //~^ ERROR cannot find value `while_let` in this scope
+    }
+    'for_loop: for _ in 0..3 {
+        //~^ WARN unused label
+        for_loop;
+        //~^ ERROR cannot find value `for_loop` in this scope
+    };
     'LOOP: loop {
+        //~^ WARN unused label
         LOOP;
         //~^ ERROR cannot find value `LOOP` in this scope
     };
+}
+
+fn foo() {
+    'LOOP: loop {
+        break LOOP;
+        //~^ ERROR cannot find value `LOOP` in this scope
+    };
     'while_loop: while true { //~ WARN denote infinite loops with
-        while_loop;
+        break while_loop;
         //~^ ERROR cannot find value `while_loop` in this scope
     };
     'while_let: while let Some(_) = Some(()) {
-        while_let;
+        break while_let;
         //~^ ERROR cannot find value `while_let` in this scope
     }
     'for_loop: for _ in 0..3 {
-        for_loop;
+        break for_loop;
         //~^ ERROR cannot find value `for_loop` in this scope
     };
 }
+
+fn bar() {
+    let foo = ();
+    'while_loop: while true { //~ WARN denote infinite loops with
+        //~^ WARN unused label
+        break foo;
+        //~^ ERROR `break` with value from a `while` loop
+    };
+    'while_let: while let Some(_) = Some(()) {
+        //~^ WARN unused label
+        break foo;
+        //~^ ERROR `break` with value from a `while` loop
+    }
+    'for_loop: for _ in 0..3 {
+        //~^ WARN unused label
+        break foo;
+        //~^ ERROR `break` with value from a `for` loop
+    };
+}
diff --git a/src/test/ui/label/label_misspelled.stderr b/src/test/ui/label/label_misspelled.stderr
index 1368ca4126c..b09695787a4 100644
--- a/src/test/ui/label/label_misspelled.stderr
+++ b/src/test/ui/label/label_misspelled.stderr
@@ -1,47 +1,206 @@
-error[E0425]: cannot find value `LOOP` in this scope
-  --> $DIR/label_misspelled.rs:3:9
-   |
-LL |         LOOP;
-   |         ^^^^
-   |         |
-   |         not found in this scope
-   |         help: a label with a similar name exists: `'LOOP`
-
 error[E0425]: cannot find value `while_loop` in this scope
-  --> $DIR/label_misspelled.rs:7:9
+  --> $DIR/label_misspelled.rs:6:9
    |
+LL |     'while_loop: while true {
+   |     ----------- a label with a similar name exists
+LL |
 LL |         while_loop;
-   |         ^^^^^^^^^^
-   |         |
-   |         not found in this scope
-   |         help: a label with a similar name exists: `'while_loop`
+   |         ^^^^^^^^^^ not found in this scope
 
 error[E0425]: cannot find value `while_let` in this scope
   --> $DIR/label_misspelled.rs:11:9
    |
+LL |     'while_let: while let Some(_) = Some(()) {
+   |     ---------- a label with a similar name exists
+LL |
 LL |         while_let;
-   |         ^^^^^^^^^
-   |         |
-   |         not found in this scope
-   |         help: a label with a similar name exists: `'while_let`
+   |         ^^^^^^^^^ not found in this scope
 
 error[E0425]: cannot find value `for_loop` in this scope
-  --> $DIR/label_misspelled.rs:15:9
+  --> $DIR/label_misspelled.rs:16:9
    |
+LL |     'for_loop: for _ in 0..3 {
+   |     --------- a label with a similar name exists
+LL |
 LL |         for_loop;
-   |         ^^^^^^^^
-   |         |
-   |         not found in this scope
-   |         help: a label with a similar name exists: `'for_loop`
+   |         ^^^^^^^^ not found in this scope
+
+error[E0425]: cannot find value `LOOP` in this scope
+  --> $DIR/label_misspelled.rs:21:9
+   |
+LL |     'LOOP: loop {
+   |     ----- a label with a similar name exists
+LL |
+LL |         LOOP;
+   |         ^^^^ not found in this scope
+
+error[E0425]: cannot find value `LOOP` in this scope
+  --> $DIR/label_misspelled.rs:28:15
+   |
+LL |     'LOOP: loop {
+   |     ----- a label with a similar name exists
+LL |         break LOOP;
+   |               ^^^^
+   |               |
+   |               not found in this scope
+   |               help: use the similarly named label: `'LOOP`
+
+error[E0425]: cannot find value `while_loop` in this scope
+  --> $DIR/label_misspelled.rs:32:15
+   |
+LL |     'while_loop: while true {
+   |     ----------- a label with a similar name exists
+LL |         break while_loop;
+   |               ^^^^^^^^^^
+   |               |
+   |               not found in this scope
+   |               help: use the similarly named label: `'while_loop`
+
+error[E0425]: cannot find value `while_let` in this scope
+  --> $DIR/label_misspelled.rs:36:15
+   |
+LL |     'while_let: while let Some(_) = Some(()) {
+   |     ---------- a label with a similar name exists
+LL |         break while_let;
+   |               ^^^^^^^^^
+   |               |
+   |               not found in this scope
+   |               help: use the similarly named label: `'while_let`
+
+error[E0425]: cannot find value `for_loop` in this scope
+  --> $DIR/label_misspelled.rs:40:15
+   |
+LL |     'for_loop: for _ in 0..3 {
+   |     --------- a label with a similar name exists
+LL |         break for_loop;
+   |               ^^^^^^^^
+   |               |
+   |               not found in this scope
+   |               help: use the similarly named label: `'for_loop`
+
+warning: unused label
+  --> $DIR/label_misspelled.rs:4:5
+   |
+LL |     'while_loop: while true {
+   |     ^^^^^^^^^^^
+   |
+note: the lint level is defined here
+  --> $DIR/label_misspelled.rs:1:9
+   |
+LL | #![warn(unused_labels)]
+   |         ^^^^^^^^^^^^^
 
 warning: denote infinite loops with `loop { ... }`
-  --> $DIR/label_misspelled.rs:6:5
+  --> $DIR/label_misspelled.rs:4:5
    |
 LL |     'while_loop: while true {
    |     ^^^^^^^^^^^^^^^^^^^^^^^ help: use `loop`
    |
    = note: `#[warn(while_true)]` on by default
 
-error: aborting due to 4 previous errors; 1 warning emitted
+warning: unused label
+  --> $DIR/label_misspelled.rs:9:5
+   |
+LL |     'while_let: while let Some(_) = Some(()) {
+   |     ^^^^^^^^^^
+
+warning: unused label
+  --> $DIR/label_misspelled.rs:14:5
+   |
+LL |     'for_loop: for _ in 0..3 {
+   |     ^^^^^^^^^
+
+warning: unused label
+  --> $DIR/label_misspelled.rs:19:5
+   |
+LL |     'LOOP: loop {
+   |     ^^^^^
+
+warning: denote infinite loops with `loop { ... }`
+  --> $DIR/label_misspelled.rs:31:5
+   |
+LL |     'while_loop: while true {
+   |     ^^^^^^^^^^^^^^^^^^^^^^^ help: use `loop`
+
+warning: unused label
+  --> $DIR/label_misspelled.rs:47:5
+   |
+LL |     'while_loop: while true {
+   |     ^^^^^^^^^^^
+
+warning: denote infinite loops with `loop { ... }`
+  --> $DIR/label_misspelled.rs:47:5
+   |
+LL |     'while_loop: while true {
+   |     ^^^^^^^^^^^^^^^^^^^^^^^ help: use `loop`
+
+warning: unused label
+  --> $DIR/label_misspelled.rs:52:5
+   |
+LL |     'while_let: while let Some(_) = Some(()) {
+   |     ^^^^^^^^^^
+
+warning: unused label
+  --> $DIR/label_misspelled.rs:57:5
+   |
+LL |     'for_loop: for _ in 0..3 {
+   |     ^^^^^^^^^
+
+error[E0571]: `break` with value from a `while` loop
+  --> $DIR/label_misspelled.rs:49:9
+   |
+LL |     'while_loop: while true {
+   |     ----------------------- you can't `break` with a value in a `while` loop
+LL |
+LL |         break foo;
+   |         ^^^^^^^^^ can only break with a value inside `loop` or breakable block
+   |
+help: use `break` on its own without a value inside this `while` loop
+   |
+LL |         break;
+   |         ^^^^^
+help: alternatively, you might have meant to use the available loop label
+   |
+LL |         break 'while_loop;
+   |               ^^^^^^^^^^^
+
+error[E0571]: `break` with value from a `while` loop
+  --> $DIR/label_misspelled.rs:54:9
+   |
+LL |     'while_let: while let Some(_) = Some(()) {
+   |     ---------------------------------------- you can't `break` with a value in a `while` loop
+LL |
+LL |         break foo;
+   |         ^^^^^^^^^ can only break with a value inside `loop` or breakable block
+   |
+help: use `break` on its own without a value inside this `while` loop
+   |
+LL |         break;
+   |         ^^^^^
+help: alternatively, you might have meant to use the available loop label
+   |
+LL |         break 'while_let;
+   |               ^^^^^^^^^^
+
+error[E0571]: `break` with value from a `for` loop
+  --> $DIR/label_misspelled.rs:59:9
+   |
+LL |     'for_loop: for _ in 0..3 {
+   |     ------------------------ you can't `break` with a value in a `for` loop
+LL |
+LL |         break foo;
+   |         ^^^^^^^^^ can only break with a value inside `loop` or breakable block
+   |
+help: use `break` on its own without a value inside this `for` loop
+   |
+LL |         break;
+   |         ^^^^^
+help: alternatively, you might have meant to use the available loop label
+   |
+LL |         break 'for_loop;
+   |               ^^^^^^^^^
+
+error: aborting due to 11 previous errors; 10 warnings emitted
 
-For more information about this error, try `rustc --explain E0425`.
+Some errors have detailed explanations: E0425, E0571.
+For more information about an error, try `rustc --explain E0425`.
diff --git a/src/test/ui/label/label_misspelled_2.rs b/src/test/ui/label/label_misspelled_2.rs
new file mode 100644
index 00000000000..55bbe6b30a5
--- /dev/null
+++ b/src/test/ui/label/label_misspelled_2.rs
@@ -0,0 +1,16 @@
+#![warn(unused_labels)]
+
+fn main() {
+    'a: for _ in 0..1 {
+        break 'a;
+    }
+    'b: for _ in 0..1 {
+        break b; //~ ERROR cannot find value `b` in this scope
+    }
+    c: for _ in 0..1 { //~ ERROR malformed loop label
+        break 'c;
+    }
+    d: for _ in 0..1 { //~ ERROR malformed loop label
+        break d; //~ ERROR cannot find value `d` in this scope
+    }
+}
diff --git a/src/test/ui/label/label_misspelled_2.stderr b/src/test/ui/label/label_misspelled_2.stderr
new file mode 100644
index 00000000000..960646d9894
--- /dev/null
+++ b/src/test/ui/label/label_misspelled_2.stderr
@@ -0,0 +1,37 @@
+error: malformed loop label
+  --> $DIR/label_misspelled_2.rs:10:5
+   |
+LL |     c: for _ in 0..1 {
+   |     ^ help: use the correct loop label format: `'c`
+
+error: malformed loop label
+  --> $DIR/label_misspelled_2.rs:13:5
+   |
+LL |     d: for _ in 0..1 {
+   |     ^ help: use the correct loop label format: `'d`
+
+error[E0425]: cannot find value `b` in this scope
+  --> $DIR/label_misspelled_2.rs:8:15
+   |
+LL |     'b: for _ in 0..1 {
+   |     -- a label with a similar name exists
+LL |         break b;
+   |               ^
+   |               |
+   |               not found in this scope
+   |               help: use the similarly named label: `'b`
+
+error[E0425]: cannot find value `d` in this scope
+  --> $DIR/label_misspelled_2.rs:14:15
+   |
+LL |     d: for _ in 0..1 {
+   |     - a label with a similar name exists
+LL |         break d;
+   |               ^
+   |               |
+   |               not found in this scope
+   |               help: use the similarly named label: `'d`
+
+error: aborting due to 4 previous errors
+
+For more information about this error, try `rustc --explain E0425`.
diff --git a/src/test/ui/loops/loop-break-value-no-repeat.stderr b/src/test/ui/loops/loop-break-value-no-repeat.stderr
index ff93e9220e9..1c0d39a6e5a 100644
--- a/src/test/ui/loops/loop-break-value-no-repeat.stderr
+++ b/src/test/ui/loops/loop-break-value-no-repeat.stderr
@@ -1,10 +1,12 @@
 error[E0571]: `break` with value from a `for` loop
   --> $DIR/loop-break-value-no-repeat.rs:12:9
    |
+LL |     for _ in &[1,2,3] {
+   |     ----------------- you can't `break` with a value in a `for` loop
 LL |         break 22
    |         ^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `for` loop
+help: use `break` on its own without a value inside this `for` loop
    |
 LL |         break
    |         ^^^^^
diff --git a/src/test/ui/loops/loop-break-value.rs b/src/test/ui/loops/loop-break-value.rs
index 8a080cfdf49..51c9a36a039 100644
--- a/src/test/ui/loops/loop-break-value.rs
+++ b/src/test/ui/loops/loop-break-value.rs
@@ -94,6 +94,5 @@ fn main() {
     'LOOP: for _ in 0 .. 9 {
         break LOOP;
         //~^ ERROR cannot find value `LOOP` in this scope
-        //~| ERROR `break` with value from a `for` loop
     }
 }
diff --git a/src/test/ui/loops/loop-break-value.stderr b/src/test/ui/loops/loop-break-value.stderr
index 0237435c8b4..adb099f9b17 100644
--- a/src/test/ui/loops/loop-break-value.stderr
+++ b/src/test/ui/loops/loop-break-value.stderr
@@ -1,11 +1,13 @@
 error[E0425]: cannot find value `LOOP` in this scope
   --> $DIR/loop-break-value.rs:95:15
    |
+LL |     'LOOP: for _ in 0 .. 9 {
+   |     ----- a label with a similar name exists
 LL |         break LOOP;
    |               ^^^^
    |               |
    |               not found in this scope
-   |               help: a label with a similar name exists: `'LOOP`
+   |               help: use the similarly named label: `'LOOP`
 
 warning: denote infinite loops with `loop { ... }`
   --> $DIR/loop-break-value.rs:26:5
@@ -18,32 +20,44 @@ LL |     'while_loop: while true {
 error[E0571]: `break` with value from a `while` loop
   --> $DIR/loop-break-value.rs:28:9
    |
+LL |     'while_loop: while true {
+   |     ----------------------- you can't `break` with a value in a `while` loop
+LL |         break;
 LL |         break ();
    |         ^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `while` loop
+help: use `break` on its own without a value inside this `while` loop
    |
 LL |         break;
    |         ^^^^^
+help: alternatively, you might have meant to use the available loop label
+   |
+LL |         break 'while_loop;
+   |               ^^^^^^^^^^^
 
 error[E0571]: `break` with value from a `while` loop
   --> $DIR/loop-break-value.rs:30:13
    |
+LL |     'while_loop: while true {
+   |     ----------------------- you can't `break` with a value in a `while` loop
+...
 LL |             break 'while_loop 123;
    |             ^^^^^^^^^^^^^^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `while` loop
+help: use `break` on its own without a value inside this `while` loop
    |
-LL |             break;
-   |             ^^^^^
+LL |             break 'while_loop;
+   |             ^^^^^^^^^^^^^^^^^
 
 error[E0571]: `break` with value from a `while` loop
   --> $DIR/loop-break-value.rs:38:12
    |
+LL |     while let Some(_) = Some(()) {
+   |     ---------------------------- you can't `break` with a value in a `while` loop
 LL |         if break () {
    |            ^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `while` loop
+help: use `break` on its own without a value inside this `while` loop
    |
 LL |         if break {
    |            ^^^^^
@@ -51,10 +65,12 @@ LL |         if break {
 error[E0571]: `break` with value from a `while` loop
   --> $DIR/loop-break-value.rs:43:9
    |
+LL |     while let Some(_) = Some(()) {
+   |     ---------------------------- you can't `break` with a value in a `while` loop
 LL |         break None;
    |         ^^^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `while` loop
+help: use `break` on its own without a value inside this `while` loop
    |
 LL |         break;
    |         ^^^^^
@@ -62,21 +78,26 @@ LL |         break;
 error[E0571]: `break` with value from a `while` loop
   --> $DIR/loop-break-value.rs:49:13
    |
+LL |     'while_let_loop: while let Some(_) = Some(()) {
+   |     --------------------------------------------- you can't `break` with a value in a `while` loop
+LL |         loop {
 LL |             break 'while_let_loop "nope";
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `while` loop
+help: use `break` on its own without a value inside this `while` loop
    |
-LL |             break;
-   |             ^^^^^
+LL |             break 'while_let_loop;
+   |             ^^^^^^^^^^^^^^^^^^^^^
 
 error[E0571]: `break` with value from a `for` loop
   --> $DIR/loop-break-value.rs:56:9
    |
+LL |     for _ in &[1,2,3] {
+   |     ----------------- you can't `break` with a value in a `for` loop
 LL |         break ();
    |         ^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `for` loop
+help: use `break` on its own without a value inside this `for` loop
    |
 LL |         break;
    |         ^^^^^
@@ -84,10 +105,13 @@ LL |         break;
 error[E0571]: `break` with value from a `for` loop
   --> $DIR/loop-break-value.rs:57:9
    |
+LL |     for _ in &[1,2,3] {
+   |     ----------------- you can't `break` with a value in a `for` loop
+LL |         break ();
 LL |         break [()];
    |         ^^^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `for` loop
+help: use `break` on its own without a value inside this `for` loop
    |
 LL |         break;
    |         ^^^^^
@@ -95,24 +119,16 @@ LL |         break;
 error[E0571]: `break` with value from a `for` loop
   --> $DIR/loop-break-value.rs:64:13
    |
+LL |     'for_loop: for _ in &[1,2,3] {
+   |     ---------------------------- you can't `break` with a value in a `for` loop
+...
 LL |             break 'for_loop Some(17);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `for` loop
-   |
-LL |             break;
-   |             ^^^^^
-
-error[E0571]: `break` with value from a `for` loop
-  --> $DIR/loop-break-value.rs:95:9
-   |
-LL |         break LOOP;
-   |         ^^^^^^^^^^ can only break with a value inside `loop` or breakable block
+help: use `break` on its own without a value inside this `for` loop
    |
-help: instead, use `break` on its own without a value inside this `for` loop
-   |
-LL |         break;
-   |         ^^^^^
+LL |             break 'for_loop;
+   |             ^^^^^^^^^^^^^^^
 
 error[E0308]: mismatched types
   --> $DIR/loop-break-value.rs:4:31
@@ -171,7 +187,7 @@ LL |         break;
    |         expected integer, found `()`
    |         help: give it a value of the expected type: `break value`
 
-error: aborting due to 18 previous errors; 1 warning emitted
+error: aborting due to 17 previous errors; 1 warning emitted
 
 Some errors have detailed explanations: E0308, E0425, E0571.
 For more information about an error, try `rustc --explain E0308`.