Rollup merge of #75023 - euclio:argument-span, r=estebank

ensure arguments are included in count mismatch span

The current diagnostic isn't very helpful if the function header spans multiple lines. Lines comprising the function signature may be elided to keep the diagnostic short, but these lines are essential to fixing the error. This is made worse when the function has a body, because the last two lines of the span are then dedicated to showing the end of the body, which is irrelevant.

This PR changes the span to be a multispan made up of the header and the the arguments, ensuring they won't be elided. It also discards the function body from the span.

[Old](https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&gist=f92d9f81a8c9416f0f04e4e09923b6d4):

```
error[E0061]: this function takes 6 arguments but 1 argument was supplied
  --> src/main.rs:18:5
   |
1  | / fn bar(
2  | |     a: i32,
3  | |     b: i32,
4  | |     c: i32,
...  |
14 | |     println!("{}", f);
15 | | }
   | |_- defined here
...
18 |       bar(1);
   |       ^^^ - supplied 1 argument
   |       |
   |       expected 6 arguments
```

New:

```
error[E0061]: this function takes 6 arguments but 1 argument was supplied
  --> $DIR/not-enough-arguments.rs:28:3
   |
LL |   bar(1);
   |   ^^^ - supplied 1 argument
   |   |
   |   expected 6 arguments
   |
note: function defined here
  --> $DIR/not-enough-arguments.rs:9:1
   |
LL | / fn bar(
LL | |     a: i32,
   | |     ^^^^^^^
LL | |     b: i32,
   | |     ^^^^^^^
LL | |     c: i32,
   | |     ^^^^^^^
LL | |     d: i32,
   | |     ^^^^^^^
LL | |     e: i32,
   | |     ^^^^^^^
LL | |     f: i32,
   | |     ^^^^^^^
LL | | ) {
   | |_^
```

17 files changed, 222 insertions, 114 deletions

diff --git a/src/test/ui/arg-count-mismatch.stderr b/src/test/ui/arg-count-mismatch.stderr
index 7bc06134a69..d0577e4864a 100644
--- a/src/test/ui/arg-count-mismatch.stderr
+++ b/src/test/ui/arg-count-mismatch.stderr
@@ -1,13 +1,16 @@
 error[E0061]: this function takes 1 argument but 0 arguments were supplied
   --> $DIR/arg-count-mismatch.rs:5:28
    |
-LL | fn f(x: isize) { }
-   | -------------- defined here
-LL | 
 LL | fn main() { let i: (); i = f(); }
    |                            ^-- supplied 0 arguments
    |                            |
    |                            expected 1 argument
+   |
+note: function defined here
+  --> $DIR/arg-count-mismatch.rs:3:4
+   |
+LL | fn f(x: isize) { }
+   |    ^ --------
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/c-variadic/variadic-ffi-1.stderr b/src/test/ui/c-variadic/variadic-ffi-1.stderr
index 89ea65fd43f..6f2a6c359b5 100644
--- a/src/test/ui/c-variadic/variadic-ffi-1.stderr
+++ b/src/test/ui/c-variadic/variadic-ffi-1.stderr
@@ -7,24 +7,30 @@ LL |     fn printf(_: *const u8, ...);
 error[E0060]: this function takes at least 2 arguments but 0 arguments were supplied
   --> $DIR/variadic-ffi-1.rs:17:9
    |
-LL |     fn foo(f: isize, x: u8, ...);
-   |     ----------------------------- defined here
-...
 LL |         foo();
    |         ^^^-- supplied 0 arguments
    |         |
    |         expected at least 2 arguments
+   |
+note: function defined here
+  --> $DIR/variadic-ffi-1.rs:10:8
+   |
+LL |     fn foo(f: isize, x: u8, ...);
+   |        ^^^
 
 error[E0060]: this function takes at least 2 arguments but 1 argument was supplied
   --> $DIR/variadic-ffi-1.rs:18:9
    |
-LL |     fn foo(f: isize, x: u8, ...);
-   |     ----------------------------- defined here
-...
 LL |         foo(1);
    |         ^^^ - supplied 1 argument
    |         |
    |         expected at least 2 arguments
+   |
+note: function defined here
+  --> $DIR/variadic-ffi-1.rs:10:8
+   |
+LL |     fn foo(f: isize, x: u8, ...);
+   |        ^^^
 
 error[E0308]: mismatched types
   --> $DIR/variadic-ffi-1.rs:20:56
diff --git a/src/test/ui/c-variadic/variadic-ffi-no-fixed-args.stderr b/src/test/ui/c-variadic/variadic-ffi-no-fixed-args.stderr
index 7af38c88f43..e11ba43ca2a 100644
--- a/src/test/ui/c-variadic/variadic-ffi-no-fixed-args.stderr
+++ b/src/test/ui/c-variadic/variadic-ffi-no-fixed-args.stderr
@@ -2,7 +2,7 @@ error: C-variadic function must be declared with at least one named argument
   --> $DIR/variadic-ffi-no-fixed-args.rs:2:12
    |
 LL |     fn foo(...);
-   |            ^^^^
+   |            ^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/error-codes/E0060.stderr b/src/test/ui/error-codes/E0060.stderr
index a600592c6c2..c80014d1476 100644
--- a/src/test/ui/error-codes/E0060.stderr
+++ b/src/test/ui/error-codes/E0060.stderr
@@ -1,13 +1,16 @@
 error[E0060]: this function takes at least 1 argument but 0 arguments were supplied
   --> $DIR/E0060.rs:6:14
    |
-LL |     fn printf(_: *const u8, ...) -> u32;
-   |     ------------------------------------ defined here
-...
 LL |     unsafe { printf(); }
    |              ^^^^^^-- supplied 0 arguments
    |              |
    |              expected at least 1 argument
+   |
+note: function defined here
+  --> $DIR/E0060.rs:2:8
+   |
+LL |     fn printf(_: *const u8, ...) -> u32;
+   |        ^^^^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/error-codes/E0061.stderr b/src/test/ui/error-codes/E0061.stderr
index dfefa0df313..98488a2d298 100644
--- a/src/test/ui/error-codes/E0061.stderr
+++ b/src/test/ui/error-codes/E0061.stderr
@@ -1,24 +1,30 @@
 error[E0061]: this function takes 2 arguments but 1 argument was supplied
   --> $DIR/E0061.rs:6:5
    |
-LL | fn f(a: u16, b: &str) {}
-   | --------------------- defined here
-...
 LL |     f(0);
    |     ^ - supplied 1 argument
    |     |
    |     expected 2 arguments
+   |
+note: function defined here
+  --> $DIR/E0061.rs:1:4
+   |
+LL | fn f(a: u16, b: &str) {}
+   |    ^ ------  -------
 
 error[E0061]: this function takes 1 argument but 0 arguments were supplied
   --> $DIR/E0061.rs:10:5
    |
-LL | fn f2(a: u16) {}
-   | ------------- defined here
-...
 LL |     f2();
    |     ^^-- supplied 0 arguments
    |     |
    |     expected 1 argument
+   |
+note: function defined here
+  --> $DIR/E0061.rs:3:4
+   |
+LL | fn f2(a: u16) {}
+   |    ^^ ------
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/hrtb/issue-58451.stderr b/src/test/ui/hrtb/issue-58451.stderr
index bd08fc1bfae..2cc1c7a2e72 100644
--- a/src/test/ui/hrtb/issue-58451.stderr
+++ b/src/test/ui/hrtb/issue-58451.stderr
@@ -1,16 +1,16 @@
 error[E0061]: this function takes 1 argument but 0 arguments were supplied
   --> $DIR/issue-58451.rs:12:9
    |
-LL | / fn f<I>(i: I)
-LL | | where
-LL | |     I: IntoIterator,
-LL | |     I::Item: for<'a> Into<&'a ()>,
-   | |__________________________________- defined here
-...
-LL |       f(&[f()]);
-   |           ^-- supplied 0 arguments
-   |           |
-   |           expected 1 argument
+LL |     f(&[f()]);
+   |         ^-- supplied 0 arguments
+   |         |
+   |         expected 1 argument
+   |
+note: function defined here
+  --> $DIR/issue-58451.rs:5:4
+   |
+LL | fn f<I>(i: I)
+   |    ^    ----
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/issues/issue-18819.stderr b/src/test/ui/issues/issue-18819.stderr
index a952c9b46c9..b10d26abe34 100644
--- a/src/test/ui/issues/issue-18819.stderr
+++ b/src/test/ui/issues/issue-18819.stderr
@@ -1,13 +1,16 @@
 error[E0061]: this function takes 2 arguments but 1 argument was supplied
   --> $DIR/issue-18819.rs:16:5
    |
-LL | fn print_x(_: &dyn Foo<Item=bool>, extra: &str) {
-   | ----------------------------------------------- defined here
-...
 LL |     print_x(X);
    |     ^^^^^^^ - supplied 1 argument
    |     |
    |     expected 2 arguments
+   |
+note: function defined here
+  --> $DIR/issue-18819.rs:11:4
+   |
+LL | fn print_x(_: &dyn Foo<Item=bool>, extra: &str) {
+   |    ^^^^^^^ ----------------------  -----------
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/issues/issue-26094.stderr b/src/test/ui/issues/issue-26094.stderr
index 2038d88bf46..a6f1ac9286c 100644
--- a/src/test/ui/issues/issue-26094.stderr
+++ b/src/test/ui/issues/issue-26094.stderr
@@ -4,11 +4,14 @@ error[E0061]: this function takes 0 arguments but 1 argument was supplied
 LL |         $other(None)
    |                ---- supplied 1 argument
 ...
-LL | fn some_function() {}
-   | ------------------ defined here
-...
 LL |     some_macro!(some_function);
    |                 ^^^^^^^^^^^^^ expected 0 arguments
+   |
+note: function defined here
+  --> $DIR/issue-26094.rs:7:4
+   |
+LL | fn some_function() {}
+   |    ^^^^^^^^^^^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/issues/issue-4935.stderr b/src/test/ui/issues/issue-4935.stderr
index 0cc686e1cf8..03b9b91edef 100644
--- a/src/test/ui/issues/issue-4935.stderr
+++ b/src/test/ui/issues/issue-4935.stderr
@@ -1,13 +1,16 @@
 error[E0061]: this function takes 1 argument but 2 arguments were supplied
   --> $DIR/issue-4935.rs:5:13
    |
-LL | fn foo(a: usize) {}
-   | ---------------- defined here
-LL |
 LL | fn main() { foo(5, 6) }
    |             ^^^ -  - supplied 2 arguments
    |             |
    |             expected 1 argument
+   |
+note: function defined here
+  --> $DIR/issue-4935.rs:3:4
+   |
+LL | fn foo(a: usize) {}
+   |    ^^^ --------
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/methods/method-call-err-msg.stderr b/src/test/ui/methods/method-call-err-msg.stderr
index b0d1bb9823b..60f9eeeca27 100644
--- a/src/test/ui/methods/method-call-err-msg.stderr
+++ b/src/test/ui/methods/method-call-err-msg.stderr
@@ -1,35 +1,44 @@
 error[E0061]: this function takes 0 arguments but 1 argument was supplied
   --> $DIR/method-call-err-msg.rs:13:7
    |
-LL |     fn zero(self) -> Foo { self }
-   |     -------------------- defined here
-...
 LL |     x.zero(0)
    |       ^^^^ - supplied 1 argument
    |       |
    |       expected 0 arguments
+   |
+note: associated function defined here
+  --> $DIR/method-call-err-msg.rs:5:8
+   |
+LL |     fn zero(self) -> Foo { self }
+   |        ^^^^ ----
 
 error[E0061]: this function takes 1 argument but 0 arguments were supplied
   --> $DIR/method-call-err-msg.rs:14:7
    |
-LL |     fn one(self, _: isize) -> Foo { self }
-   |     ----------------------------- defined here
-...
 LL |      .one()
    |       ^^^- supplied 0 arguments
    |       |
    |       expected 1 argument
+   |
+note: associated function defined here
+  --> $DIR/method-call-err-msg.rs:6:8
+   |
+LL |     fn one(self, _: isize) -> Foo { self }
+   |        ^^^ ----  --------
 
 error[E0061]: this function takes 2 arguments but 1 argument was supplied
   --> $DIR/method-call-err-msg.rs:15:7
    |
-LL |     fn two(self, _: isize, _: isize) -> Foo { self }
-   |     --------------------------------------- defined here
-...
 LL |      .two(0);
    |       ^^^ - supplied 1 argument
    |       |
    |       expected 2 arguments
+   |
+note: associated function defined here
+  --> $DIR/method-call-err-msg.rs:7:8
+   |
+LL |     fn two(self, _: isize, _: isize) -> Foo { self }
+   |        ^^^ ----  --------  --------
 
 error[E0599]: no method named `take` found for struct `Foo` in the current scope
   --> $DIR/method-call-err-msg.rs:19:7
@@ -53,13 +62,16 @@ LL |      .take()
 error[E0061]: this function takes 3 arguments but 0 arguments were supplied
   --> $DIR/method-call-err-msg.rs:21:7
    |
-LL |     fn three<T>(self, _: T, _: T, _: T) -> Foo { self }
-   |     ------------------------------------------ defined here
-...
 LL |     y.three::<usize>();
    |       ^^^^^--------- supplied 0 arguments
    |       |
    |       expected 3 arguments
+   |
+note: associated function defined here
+  --> $DIR/method-call-err-msg.rs:8:8
+   |
+LL |     fn three<T>(self, _: T, _: T, _: T) -> Foo { self }
+   |        ^^^^^    ----  ----  ----  ----
 
 error: aborting due to 5 previous errors
 
diff --git a/src/test/ui/mismatched_types/issue-38371.stderr b/src/test/ui/mismatched_types/issue-38371.stderr
index c2bce305877..5d2ce9302ec 100644
--- a/src/test/ui/mismatched_types/issue-38371.stderr
+++ b/src/test/ui/mismatched_types/issue-38371.stderr
@@ -2,7 +2,7 @@ error[E0308]: mismatched types
   --> $DIR/issue-38371.rs:4:8
    |
 LL | fn foo(&foo: Foo) {
-   |        ^^^^------
+   |        ^^^^-----
    |        |     |
    |        |     expected due to this
    |        expected struct `Foo`, found reference
diff --git a/src/test/ui/not-enough-arguments.rs b/src/test/ui/not-enough-arguments.rs
index 631bb1dd274..42476255188 100644
--- a/src/test/ui/not-enough-arguments.rs
+++ b/src/test/ui/not-enough-arguments.rs
@@ -6,7 +6,26 @@ fn foo(a: isize, b: isize, c: isize, d:isize) {
   panic!();
 }
 
+// Check that all arguments are shown in the error message, even if they're across multiple lines.
+fn bar(
+    a: i32,
+    b: i32,
+    c: i32,
+    d: i32,
+    e: i32,
+    f: i32,
+) {
+    println!("{}", a);
+    println!("{}", b);
+    println!("{}", c);
+    println!("{}", d);
+    println!("{}", e);
+    println!("{}", f);
+}
+
 fn main() {
   foo(1, 2, 3);
   //~^ ERROR this function takes 4 arguments but 3
+  bar(1, 2, 3);
+  //~^ ERROR this function takes 6 arguments but 3
 }
diff --git a/src/test/ui/not-enough-arguments.stderr b/src/test/ui/not-enough-arguments.stderr
index f2b57f71400..df957837241 100644
--- a/src/test/ui/not-enough-arguments.stderr
+++ b/src/test/ui/not-enough-arguments.stderr
@@ -1,14 +1,43 @@
 error[E0061]: this function takes 4 arguments but 3 arguments were supplied
-  --> $DIR/not-enough-arguments.rs:10:3
+  --> $DIR/not-enough-arguments.rs:27:3
    |
-LL | fn foo(a: isize, b: isize, c: isize, d:isize) {
-   | --------------------------------------------- defined here
-...
 LL |   foo(1, 2, 3);
    |   ^^^ -  -  - supplied 3 arguments
    |   |
    |   expected 4 arguments
+   |
+note: function defined here
+  --> $DIR/not-enough-arguments.rs:5:4
+   |
+LL | fn foo(a: isize, b: isize, c: isize, d:isize) {
+   |    ^^^ --------  --------  --------  -------
+
+error[E0061]: this function takes 6 arguments but 3 arguments were supplied
+  --> $DIR/not-enough-arguments.rs:29:3
+   |
+LL |   bar(1, 2, 3);
+   |   ^^^ -  -  - supplied 3 arguments
+   |   |
+   |   expected 6 arguments
+   |
+note: function defined here
+  --> $DIR/not-enough-arguments.rs:10:4
+   |
+LL | fn bar(
+   |    ^^^
+LL |     a: i32,
+   |     ------
+LL |     b: i32,
+   |     ------
+LL |     c: i32,
+   |     ------
+LL |     d: i32,
+   |     ------
+LL |     e: i32,
+   |     ------
+LL |     f: i32,
+   |     ------
 
-error: aborting due to previous error
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0061`.
diff --git a/src/test/ui/parser/variadic-ffi-semantic-restrictions.stderr b/src/test/ui/parser/variadic-ffi-semantic-restrictions.stderr
index 21992a29670..3f3ddfed14a 100644
--- a/src/test/ui/parser/variadic-ffi-semantic-restrictions.stderr
+++ b/src/test/ui/parser/variadic-ffi-semantic-restrictions.stderr
@@ -2,205 +2,205 @@ error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:5:19
    |
 LL | fn f1_1(x: isize, ...) {}
-   |                   ^^^^
+   |                   ^^^
 
 error: C-variadic function must be declared with at least one named argument
   --> $DIR/variadic-ffi-semantic-restrictions.rs:8:9
    |
 LL | fn f1_2(...) {}
-   |         ^^^^
+   |         ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:8:9
    |
 LL | fn f1_2(...) {}
-   |         ^^^^
+   |         ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:12:30
    |
 LL | extern "C" fn f2_1(x: isize, ...) {}
-   |                              ^^^^
+   |                              ^^^
 
 error: C-variadic function must be declared with at least one named argument
   --> $DIR/variadic-ffi-semantic-restrictions.rs:15:20
    |
 LL | extern "C" fn f2_2(...) {}
-   |                    ^^^^
+   |                    ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:15:20
    |
 LL | extern "C" fn f2_2(...) {}
-   |                    ^^^^
+   |                    ^^^
 
 error: `...` must be the last argument of a C-variadic function
   --> $DIR/variadic-ffi-semantic-restrictions.rs:19:20
    |
 LL | extern "C" fn f2_3(..., x: isize) {}
-   |                    ^^^^
+   |                    ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:19:20
    |
 LL | extern "C" fn f2_3(..., x: isize) {}
-   |                    ^^^^
+   |                    ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:23:26
    |
 LL | extern fn f3_1(x: isize, ...) {}
-   |                          ^^^^
+   |                          ^^^
 
 error: C-variadic function must be declared with at least one named argument
   --> $DIR/variadic-ffi-semantic-restrictions.rs:26:16
    |
 LL | extern fn f3_2(...) {}
-   |                ^^^^
+   |                ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:26:16
    |
 LL | extern fn f3_2(...) {}
-   |                ^^^^
+   |                ^^^
 
 error: `...` must be the last argument of a C-variadic function
   --> $DIR/variadic-ffi-semantic-restrictions.rs:30:16
    |
 LL | extern fn f3_3(..., x: isize) {}
-   |                ^^^^
+   |                ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:30:16
    |
 LL | extern fn f3_3(..., x: isize) {}
-   |                ^^^^
+   |                ^^^
 
 error: C-variadic function must be declared with at least one named argument
   --> $DIR/variadic-ffi-semantic-restrictions.rs:35:13
    |
 LL |     fn e_f1(...);
-   |             ^^^^
+   |             ^^^
 
 error: `...` must be the last argument of a C-variadic function
   --> $DIR/variadic-ffi-semantic-restrictions.rs:37:13
    |
 LL |     fn e_f2(..., x: isize);
-   |             ^^^^
+   |             ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:44:23
    |
 LL |     fn i_f1(x: isize, ...) {}
-   |                       ^^^^
+   |                       ^^^
 
 error: C-variadic function must be declared with at least one named argument
   --> $DIR/variadic-ffi-semantic-restrictions.rs:46:13
    |
 LL |     fn i_f2(...) {}
-   |             ^^^^
+   |             ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:46:13
    |
 LL |     fn i_f2(...) {}
-   |             ^^^^
+   |             ^^^
 
 error: `...` must be the last argument of a C-variadic function
   --> $DIR/variadic-ffi-semantic-restrictions.rs:49:13
    |
 LL |     fn i_f3(..., x: isize, ...) {}
-   |             ^^^^
+   |             ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:49:13
    |
 LL |     fn i_f3(..., x: isize, ...) {}
-   |             ^^^^
+   |             ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:49:28
    |
 LL |     fn i_f3(..., x: isize, ...) {}
-   |                            ^^^^
+   |                            ^^^
 
 error: `...` must be the last argument of a C-variadic function
   --> $DIR/variadic-ffi-semantic-restrictions.rs:53:13
    |
 LL |     fn i_f4(..., x: isize, ...) {}
-   |             ^^^^
+   |             ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:53:13
    |
 LL |     fn i_f4(..., x: isize, ...) {}
-   |             ^^^^
+   |             ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:53:28
    |
 LL |     fn i_f4(..., x: isize, ...) {}
-   |                            ^^^^
+   |                            ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:60:23
    |
 LL |     fn t_f1(x: isize, ...) {}
-   |                       ^^^^
+   |                       ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:62:23
    |
 LL |     fn t_f2(x: isize, ...);
-   |                       ^^^^
+   |                       ^^^
 
 error: C-variadic function must be declared with at least one named argument
   --> $DIR/variadic-ffi-semantic-restrictions.rs:64:13
    |
 LL |     fn t_f3(...) {}
-   |             ^^^^
+   |             ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:64:13
    |
 LL |     fn t_f3(...) {}
-   |             ^^^^
+   |             ^^^
 
 error: C-variadic function must be declared with at least one named argument
   --> $DIR/variadic-ffi-semantic-restrictions.rs:67:13
    |
 LL |     fn t_f4(...);
-   |             ^^^^
+   |             ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:67:13
    |
 LL |     fn t_f4(...);
-   |             ^^^^
+   |             ^^^
 
 error: `...` must be the last argument of a C-variadic function
   --> $DIR/variadic-ffi-semantic-restrictions.rs:70:13
    |
 LL |     fn t_f5(..., x: isize) {}
-   |             ^^^^
+   |             ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:70:13
    |
 LL |     fn t_f5(..., x: isize) {}
-   |             ^^^^
+   |             ^^^
 
 error: `...` must be the last argument of a C-variadic function
   --> $DIR/variadic-ffi-semantic-restrictions.rs:73:13
    |
 LL |     fn t_f6(..., x: isize);
-   |             ^^^^
+   |             ^^^
 
 error: only foreign or `unsafe extern "C" functions may be C-variadic
   --> $DIR/variadic-ffi-semantic-restrictions.rs:73:13
    |
 LL |     fn t_f6(..., x: isize);
-   |             ^^^^
+   |             ^^^
 
 error: aborting due to 34 previous errors
 
diff --git a/src/test/ui/span/issue-34264.stderr b/src/test/ui/span/issue-34264.stderr
index 40c3219bf27..5cda17fd6a1 100644
--- a/src/test/ui/span/issue-34264.stderr
+++ b/src/test/ui/span/issue-34264.stderr
@@ -53,13 +53,16 @@ LL | fn bar(_: x, y: usize) {}
 error[E0061]: this function takes 2 arguments but 3 arguments were supplied
   --> $DIR/issue-34264.rs:7:5
    |
-LL | fn foo(Option<i32>, String) {}
-   | --------------------------- defined here
-...
 LL |     foo(Some(42), 2, "");
    |     ^^^ --------  -  -- supplied 3 arguments
    |     |
    |     expected 2 arguments
+   |
+note: function defined here
+  --> $DIR/issue-34264.rs:1:4
+   |
+LL | fn foo(Option<i32>, String) {}
+   |    ^^^ -----------  ------
 
 error[E0308]: mismatched types
   --> $DIR/issue-34264.rs:8:13
@@ -70,13 +73,16 @@ LL |     bar("", "");
 error[E0061]: this function takes 2 arguments but 3 arguments were supplied
   --> $DIR/issue-34264.rs:10:5
    |
-LL | fn bar(x, y: usize) {}
-   | ------------------- defined here
-...
 LL |     bar(1, 2, 3);
    |     ^^^ -  -  - supplied 3 arguments
    |     |
    |     expected 2 arguments
+   |
+note: function defined here
+  --> $DIR/issue-34264.rs:3:4
+   |
+LL | fn bar(x, y: usize) {}
+   |    ^^^ -  --------
 
 error: aborting due to 6 previous errors
 
diff --git a/src/test/ui/span/missing-unit-argument.stderr b/src/test/ui/span/missing-unit-argument.stderr
index f6344fba3d3..b15da2cb479 100644
--- a/src/test/ui/span/missing-unit-argument.stderr
+++ b/src/test/ui/span/missing-unit-argument.stderr
@@ -12,34 +12,42 @@ LL |     let _: Result<(), String> = Ok(());
 error[E0061]: this function takes 2 arguments but 0 arguments were supplied
   --> $DIR/missing-unit-argument.rs:12:5
    |
-LL | fn foo(():(), ():()) {}
-   | -------------------- defined here
-...
 LL |     foo();
    |     ^^^-- supplied 0 arguments
    |     |
    |     expected 2 arguments
+   |
+note: function defined here
+  --> $DIR/missing-unit-argument.rs:1:4
+   |
+LL | fn foo(():(), ():()) {}
+   |    ^^^ -----  -----
 
 error[E0061]: this function takes 2 arguments but 1 argument was supplied
   --> $DIR/missing-unit-argument.rs:13:5
    |
-LL | fn foo(():(), ():()) {}
-   | -------------------- defined here
-...
 LL |     foo(());
    |     ^^^ -- supplied 1 argument
    |     |
    |     expected 2 arguments
+   |
+note: function defined here
+  --> $DIR/missing-unit-argument.rs:1:4
+   |
+LL | fn foo(():(), ():()) {}
+   |    ^^^ -----  -----
 
 error[E0061]: this function takes 1 argument but 0 arguments were supplied
   --> $DIR/missing-unit-argument.rs:14:5
    |
-LL | fn bar(():()) {}
-   | ------------- defined here
-...
 LL |     bar();
    |     ^^^-- supplied 0 arguments
    |
+note: function defined here
+  --> $DIR/missing-unit-argument.rs:2:4
+   |
+LL | fn bar(():()) {}
+   |    ^^^ -----
 help: expected the unit value `()`; create it with empty parentheses
    |
 LL |     bar(());
@@ -48,12 +56,14 @@ LL |     bar(());
 error[E0061]: this function takes 1 argument but 0 arguments were supplied
   --> $DIR/missing-unit-argument.rs:15:7
    |
-LL |     fn baz(self, (): ()) { }
-   |     -------------------- defined here
-...
 LL |     S.baz();
    |       ^^^- supplied 0 arguments
    |
+note: associated function defined here
+  --> $DIR/missing-unit-argument.rs:6:8
+   |
+LL |     fn baz(self, (): ()) { }
+   |        ^^^ ----  ------
 help: expected the unit value `()`; create it with empty parentheses
    |
 LL |     S.baz(());
@@ -62,12 +72,14 @@ LL |     S.baz(());
 error[E0061]: this function takes 1 argument but 0 arguments were supplied
   --> $DIR/missing-unit-argument.rs:16:7
    |
-LL |     fn generic<T>(self, _: T) { }
-   |     ------------------------- defined here
-...
 LL |     S.generic::<()>();
    |       ^^^^^^^------ supplied 0 arguments
    |
+note: associated function defined here
+  --> $DIR/missing-unit-argument.rs:7:8
+   |
+LL |     fn generic<T>(self, _: T) { }
+   |        ^^^^^^^    ----  ----
 help: expected the unit value `()`; create it with empty parentheses
    |
 LL |     S.generic::<()>(());
diff --git a/src/test/ui/type-alias-enum-variants/enum-variant-priority-higher-than-other-inherent.stderr b/src/test/ui/type-alias-enum-variants/enum-variant-priority-higher-than-other-inherent.stderr
index 46e7dd0c517..20e26058451 100644
--- a/src/test/ui/type-alias-enum-variants/enum-variant-priority-higher-than-other-inherent.stderr
+++ b/src/test/ui/type-alias-enum-variants/enum-variant-priority-higher-than-other-inherent.stderr
@@ -1,13 +1,16 @@
 error[E0061]: this function takes 1 argument but 0 arguments were supplied
   --> $DIR/enum-variant-priority-higher-than-other-inherent.rs:21:5
    |
-LL |     V(u8)
-   |     ----- defined here
-...
 LL |     <E>::V();
    |     ^^^^^^-- supplied 0 arguments
    |     |
    |     expected 1 argument
+   |
+note: tuple variant defined here
+  --> $DIR/enum-variant-priority-higher-than-other-inherent.rs:5:5
+   |
+LL |     V(u8)
+   |     ^^^^^
 
 error[E0308]: mismatched types
   --> $DIR/enum-variant-priority-higher-than-other-inherent.rs:22:17