Auto merge of #124679 - Urgau:check-cfg-structured-cli-errors, r=nnethercote

Improve check-cfg CLI errors with more structured diagnostics

This PR improve check-cfg CLI errors with more structured diagnostics.

In particular it now shows the statement where the error occurred, what kind lit it is, as well as pointing users to the doc for more details.

`@rustbot` label +F-check-cfg

28 files changed, 151 insertions, 34 deletions

diff --git a/Cargo.lock b/Cargo.lock
index e5b5543b367..84f7d21239a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4162,6 +4162,7 @@ dependencies = [
  "rustc_ast",
  "rustc_ast_lowering",
  "rustc_ast_passes",
+ "rustc_ast_pretty",
  "rustc_attr",
  "rustc_borrowck",
  "rustc_builtin_macros",
diff --git a/compiler/rustc_ast/src/token.rs b/compiler/rustc_ast/src/token.rs
index 6e946530749..72f89737f99 100644
--- a/compiler/rustc_ast/src/token.rs
+++ b/compiler/rustc_ast/src/token.rs
@@ -167,7 +167,7 @@ impl LitKind {
 
     pub fn descr(self) -> &'static str {
         match self {
-            Bool => panic!("literal token contains `Lit::Bool`"),
+            Bool => "boolean",
             Byte => "byte",
             Char => "char",
             Integer => "integer",
diff --git a/compiler/rustc_interface/Cargo.toml b/compiler/rustc_interface/Cargo.toml
index 0e90836145e..4b3b0728f38 100644
--- a/compiler/rustc_interface/Cargo.toml
+++ b/compiler/rustc_interface/Cargo.toml
@@ -10,6 +10,7 @@ rustc-rayon-core = { version = "0.5.0", optional = true }
 rustc_ast = { path = "../rustc_ast" }
 rustc_ast_lowering = { path = "../rustc_ast_lowering" }
 rustc_ast_passes = { path = "../rustc_ast_passes" }
+rustc_ast_pretty = { path = "../rustc_ast_pretty" }
 rustc_attr = { path = "../rustc_attr" }
 rustc_borrowck = { path = "../rustc_borrowck" }
 rustc_builtin_macros = { path = "../rustc_builtin_macros" }
diff --git a/compiler/rustc_interface/src/interface.rs b/compiler/rustc_interface/src/interface.rs
index c5b81dbd679..55304bbbd92 100644
--- a/compiler/rustc_interface/src/interface.rs
+++ b/compiler/rustc_interface/src/interface.rs
@@ -120,14 +120,45 @@ pub(crate) fn parse_check_cfg(dcx: &DiagCtxt, specs: Vec<String>) -> CheckCfg {
         );
         let filename = FileName::cfg_spec_source_code(&s);
 
+        const VISIT: &str =
+            "visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details";
+
         macro_rules! error {
             ($reason:expr) => {
                 #[allow(rustc::untranslatable_diagnostic)]
                 #[allow(rustc::diagnostic_outside_of_impl)]
-                dcx.fatal(format!(
-                    concat!("invalid `--check-cfg` argument: `{}` (", $reason, ")"),
-                    s
-                ))
+                {
+                    let mut diag =
+                        dcx.struct_fatal(format!("invalid `--check-cfg` argument: `{s}`"));
+                    diag.note($reason);
+                    diag.note(VISIT);
+                    diag.emit()
+                }
+            };
+            (in $arg:expr, $reason:expr) => {
+                #[allow(rustc::untranslatable_diagnostic)]
+                #[allow(rustc::diagnostic_outside_of_impl)]
+                {
+                    let mut diag =
+                        dcx.struct_fatal(format!("invalid `--check-cfg` argument: `{s}`"));
+
+                    let pparg = rustc_ast_pretty::pprust::meta_list_item_to_string($arg);
+                    if let Some(lit) = $arg.lit() {
+                        let (lit_kind_article, lit_kind_descr) = {
+                            let lit_kind = lit.as_token_lit().kind;
+                            (lit_kind.article(), lit_kind.descr())
+                        };
+                        diag.note(format!(
+                            "`{pparg}` is {lit_kind_article} {lit_kind_descr} literal"
+                        ));
+                    } else {
+                        diag.note(format!("`{pparg}` is invalid"));
+                    }
+
+                    diag.note($reason);
+                    diag.note(VISIT);
+                    diag.emit()
+                }
             };
         }
 
@@ -183,7 +214,7 @@ pub(crate) fn parse_check_cfg(dcx: &DiagCtxt, specs: Vec<String>) -> CheckCfg {
                 }
                 any_specified = true;
                 if !args.is_empty() {
-                    error!("`any()` must be empty");
+                    error!(in arg, "`any()` takes no argument");
                 }
             } else if arg.has_name(sym::values)
                 && let Some(args) = arg.meta_item_list()
@@ -202,25 +233,25 @@ pub(crate) fn parse_check_cfg(dcx: &DiagCtxt, specs: Vec<String>) -> CheckCfg {
                         && let Some(args) = arg.meta_item_list()
                     {
                         if values_any_specified {
-                            error!("`any()` in `values()` cannot be specified multiple times");
+                            error!(in arg, "`any()` in `values()` cannot be specified multiple times");
                         }
                         values_any_specified = true;
                         if !args.is_empty() {
-                            error!("`any()` must be empty");
+                            error!(in arg, "`any()` in `values()` takes no argument");
                         }
                     } else if arg.has_name(sym::none)
                         && let Some(args) = arg.meta_item_list()
                     {
                         values.insert(None);
                         if !args.is_empty() {
-                            error!("`none()` must be empty");
+                            error!(in arg, "`none()` in `values()` takes no argument");
                         }
                     } else {
-                        error!("`values()` arguments must be string literals, `none()` or `any()`");
+                        error!(in arg, "`values()` arguments must be string literals, `none()` or `any()`");
                     }
                 }
             } else {
-                error!("`cfg()` arguments must be simple identifiers, `any()` or `values(...)`");
+                error!(in arg, "`cfg()` arguments must be simple identifiers, `any()` or `values(...)`");
             }
         }
 
diff --git a/tests/ui/check-cfg/invalid-arguments.any_values.stderr b/tests/ui/check-cfg/invalid-arguments.any_values.stderr
index f9a9c4a6e13..65ef5155fa1 100644
--- a/tests/ui/check-cfg/invalid-arguments.any_values.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.any_values.stderr
@@ -1,2 +1,5 @@
-error: invalid `--check-cfg` argument: `cfg(any(),values())` (`values()` cannot be specified before the names)
+error: invalid `--check-cfg` argument: `cfg(any(),values())`
+   |
+   = note: `values()` cannot be specified before the names
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.anything_else.stderr b/tests/ui/check-cfg/invalid-arguments.anything_else.stderr
index 925664bb3fc..f3bc0b782e2 100644
--- a/tests/ui/check-cfg/invalid-arguments.anything_else.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.anything_else.stderr
@@ -1,2 +1,5 @@
-error: invalid `--check-cfg` argument: `anything_else(...)` (expected `cfg(name, values("value1", "value2", ... "valueN"))`)
+error: invalid `--check-cfg` argument: `anything_else(...)`
+   |
+   = note: expected `cfg(name, values("value1", "value2", ... "valueN"))`
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.boolean.stderr b/tests/ui/check-cfg/invalid-arguments.boolean.stderr
new file mode 100644
index 00000000000..18734de9dac
--- /dev/null
+++ b/tests/ui/check-cfg/invalid-arguments.boolean.stderr
@@ -0,0 +1,6 @@
+error: invalid `--check-cfg` argument: `cfg(true)`
+   |
+   = note: `true` is a boolean literal
+   = note: `cfg()` arguments must be simple identifiers, `any()` or `values(...)`
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
+
diff --git a/tests/ui/check-cfg/invalid-arguments.cfg_none.stderr b/tests/ui/check-cfg/invalid-arguments.cfg_none.stderr
index 7992dbdff00..ef464260c29 100644
--- a/tests/ui/check-cfg/invalid-arguments.cfg_none.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.cfg_none.stderr
@@ -1,2 +1,6 @@
-error: invalid `--check-cfg` argument: `cfg(none())` (`cfg()` arguments must be simple identifiers, `any()` or `values(...)`)
+error: invalid `--check-cfg` argument: `cfg(none())`
+   |
+   = note: `none()` is invalid
+   = note: `cfg()` arguments must be simple identifiers, `any()` or `values(...)`
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.giberich.stderr b/tests/ui/check-cfg/invalid-arguments.giberich.stderr
index d427033fcc2..3e350145491 100644
--- a/tests/ui/check-cfg/invalid-arguments.giberich.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.giberich.stderr
@@ -1,2 +1,5 @@
-error: invalid `--check-cfg` argument: `cfg(...)` (expected `cfg(name, values("value1", "value2", ... "valueN"))`)
+error: invalid `--check-cfg` argument: `cfg(...)`
+   |
+   = note: expected `cfg(name, values("value1", "value2", ... "valueN"))`
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.ident_in_values_1.stderr b/tests/ui/check-cfg/invalid-arguments.ident_in_values_1.stderr
index 90308bdcd23..cfedb7ed517 100644
--- a/tests/ui/check-cfg/invalid-arguments.ident_in_values_1.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.ident_in_values_1.stderr
@@ -1,2 +1,6 @@
-error: invalid `--check-cfg` argument: `cfg(foo,values(bar))` (`values()` arguments must be string literals, `none()` or `any()`)
+error: invalid `--check-cfg` argument: `cfg(foo,values(bar))`
+   |
+   = note: `bar` is invalid
+   = note: `values()` arguments must be string literals, `none()` or `any()`
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.ident_in_values_2.stderr b/tests/ui/check-cfg/invalid-arguments.ident_in_values_2.stderr
index 16f92a504a5..ba194862284 100644
--- a/tests/ui/check-cfg/invalid-arguments.ident_in_values_2.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.ident_in_values_2.stderr
@@ -1,2 +1,6 @@
-error: invalid `--check-cfg` argument: `cfg(foo,values("bar",bar,"bar"))` (`values()` arguments must be string literals, `none()` or `any()`)
+error: invalid `--check-cfg` argument: `cfg(foo,values("bar",bar,"bar"))`
+   |
+   = note: `bar` is invalid
+   = note: `values()` arguments must be string literals, `none()` or `any()`
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.mixed_any.stderr b/tests/ui/check-cfg/invalid-arguments.mixed_any.stderr
index 9239f8cce94..512ecbe9eda 100644
--- a/tests/ui/check-cfg/invalid-arguments.mixed_any.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.mixed_any.stderr
@@ -1,2 +1,5 @@
-error: invalid `--check-cfg` argument: `cfg(any(),values(any()))` (`values()` cannot be specified before the names)
+error: invalid `--check-cfg` argument: `cfg(any(),values(any()))`
+   |
+   = note: `values()` cannot be specified before the names
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.mixed_values_any.stderr b/tests/ui/check-cfg/invalid-arguments.mixed_values_any.stderr
index 4c406143d08..2d59b12097d 100644
--- a/tests/ui/check-cfg/invalid-arguments.mixed_values_any.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.mixed_values_any.stderr
@@ -1,2 +1,5 @@
-error: invalid `--check-cfg` argument: `cfg(foo,values("bar",any()))` (`values()` arguments cannot specify string literals and `any()` at the same time)
+error: invalid `--check-cfg` argument: `cfg(foo,values("bar",any()))`
+   |
+   = note: `values()` arguments cannot specify string literals and `any()` at the same time
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.multiple_any.stderr b/tests/ui/check-cfg/invalid-arguments.multiple_any.stderr
index 6f1db1b13c3..6eb63de4252 100644
--- a/tests/ui/check-cfg/invalid-arguments.multiple_any.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.multiple_any.stderr
@@ -1,2 +1,5 @@
-error: invalid `--check-cfg` argument: `cfg(any(),any())` (`any()` cannot be specified multiple times)
+error: invalid `--check-cfg` argument: `cfg(any(),any())`
+   |
+   = note: `any()` cannot be specified multiple times
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.multiple_values.stderr b/tests/ui/check-cfg/invalid-arguments.multiple_values.stderr
index bce305b09c3..06060078bc0 100644
--- a/tests/ui/check-cfg/invalid-arguments.multiple_values.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.multiple_values.stderr
@@ -1,2 +1,5 @@
-error: invalid `--check-cfg` argument: `cfg(foo,values(),values())` (`values()` cannot be specified multiple times)
+error: invalid `--check-cfg` argument: `cfg(foo,values(),values())`
+   |
+   = note: `values()` cannot be specified multiple times
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.multiple_values_any.stderr b/tests/ui/check-cfg/invalid-arguments.multiple_values_any.stderr
index 748ce231af7..72554ac3ead 100644
--- a/tests/ui/check-cfg/invalid-arguments.multiple_values_any.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.multiple_values_any.stderr
@@ -1,2 +1,6 @@
-error: invalid `--check-cfg` argument: `cfg(foo,values(any(),any()))` (`any()` in `values()` cannot be specified multiple times)
+error: invalid `--check-cfg` argument: `cfg(foo,values(any(),any()))`
+   |
+   = note: `any()` is invalid
+   = note: `any()` in `values()` cannot be specified multiple times
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.none_not_empty.stderr b/tests/ui/check-cfg/invalid-arguments.none_not_empty.stderr
index 0a6c6ffd42f..6e9d87bace2 100644
--- a/tests/ui/check-cfg/invalid-arguments.none_not_empty.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.none_not_empty.stderr
@@ -1,2 +1,6 @@
-error: invalid `--check-cfg` argument: `cfg(foo,values(none("test")))` (`none()` must be empty)
+error: invalid `--check-cfg` argument: `cfg(foo,values(none("test")))`
+   |
+   = note: `none("test")` is invalid
+   = note: `none()` in `values()` takes no argument
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.not_empty_any.stderr b/tests/ui/check-cfg/invalid-arguments.not_empty_any.stderr
index daf38147fe5..35eb1949ad7 100644
--- a/tests/ui/check-cfg/invalid-arguments.not_empty_any.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.not_empty_any.stderr
@@ -1,2 +1,6 @@
-error: invalid `--check-cfg` argument: `cfg(any(foo))` (`any()` must be empty)
+error: invalid `--check-cfg` argument: `cfg(any(foo))`
+   |
+   = note: `any(foo)` is invalid
+   = note: `any()` takes no argument
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.not_empty_values_any.stderr b/tests/ui/check-cfg/invalid-arguments.not_empty_values_any.stderr
index 79f83e802ca..cc41d21bec6 100644
--- a/tests/ui/check-cfg/invalid-arguments.not_empty_values_any.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.not_empty_values_any.stderr
@@ -1,2 +1,6 @@
-error: invalid `--check-cfg` argument: `cfg(foo,values(any(bar)))` (`any()` must be empty)
+error: invalid `--check-cfg` argument: `cfg(foo,values(any(bar)))`
+   |
+   = note: `any(bar)` is invalid
+   = note: `any()` in `values()` takes no argument
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.rs b/tests/ui/check-cfg/invalid-arguments.rs
index c0b58ede97f..b8588ecb4ff 100644
--- a/tests/ui/check-cfg/invalid-arguments.rs
+++ b/tests/ui/check-cfg/invalid-arguments.rs
@@ -2,7 +2,7 @@
 //
 //@ check-fail
 //@ no-auto-check-cfg
-//@ revisions: anything_else
+//@ revisions: anything_else boolean
 //@ revisions: string_for_name_1 string_for_name_2 multiple_any multiple_values
 //@ revisions: multiple_values_any not_empty_any not_empty_values_any
 //@ revisions: values_any_missing_values values_any_before_ident ident_in_values_1
@@ -11,6 +11,7 @@
 //@ revisions: none_not_empty cfg_none
 //
 //@ [anything_else]compile-flags: --check-cfg=anything_else(...)
+//@ [boolean]compile-flags: --check-cfg=cfg(true)
 //@ [string_for_name_1]compile-flags: --check-cfg=cfg("NOT_IDENT")
 //@ [string_for_name_2]compile-flags: --check-cfg=cfg(foo,"NOT_IDENT",bar)
 //@ [multiple_any]compile-flags: --check-cfg=cfg(any(),any())
diff --git a/tests/ui/check-cfg/invalid-arguments.string_for_name_1.stderr b/tests/ui/check-cfg/invalid-arguments.string_for_name_1.stderr
index c6f6834ffd3..7022b709b64 100644
--- a/tests/ui/check-cfg/invalid-arguments.string_for_name_1.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.string_for_name_1.stderr
@@ -1,2 +1,6 @@
-error: invalid `--check-cfg` argument: `cfg("NOT_IDENT")` (`cfg()` arguments must be simple identifiers, `any()` or `values(...)`)
+error: invalid `--check-cfg` argument: `cfg("NOT_IDENT")`
+   |
+   = note: `"NOT_IDENT"` is a string literal
+   = note: `cfg()` arguments must be simple identifiers, `any()` or `values(...)`
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.string_for_name_2.stderr b/tests/ui/check-cfg/invalid-arguments.string_for_name_2.stderr
index ab3dc86cd1a..ea96b913907 100644
--- a/tests/ui/check-cfg/invalid-arguments.string_for_name_2.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.string_for_name_2.stderr
@@ -1,2 +1,6 @@
-error: invalid `--check-cfg` argument: `cfg(foo,"NOT_IDENT",bar)` (`cfg()` arguments must be simple identifiers, `any()` or `values(...)`)
+error: invalid `--check-cfg` argument: `cfg(foo,"NOT_IDENT",bar)`
+   |
+   = note: `"NOT_IDENT"` is a string literal
+   = note: `cfg()` arguments must be simple identifiers, `any()` or `values(...)`
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.unknown_meta_item_1.stderr b/tests/ui/check-cfg/invalid-arguments.unknown_meta_item_1.stderr
index c04b15ec265..f82c520c62a 100644
--- a/tests/ui/check-cfg/invalid-arguments.unknown_meta_item_1.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.unknown_meta_item_1.stderr
@@ -1,2 +1,5 @@
-error: invalid `--check-cfg` argument: `abc()` (expected `cfg(name, values("value1", "value2", ... "valueN"))`)
+error: invalid `--check-cfg` argument: `abc()`
+   |
+   = note: expected `cfg(name, values("value1", "value2", ... "valueN"))`
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.unknown_meta_item_2.stderr b/tests/ui/check-cfg/invalid-arguments.unknown_meta_item_2.stderr
index cee65f9887b..ee62c25b41c 100644
--- a/tests/ui/check-cfg/invalid-arguments.unknown_meta_item_2.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.unknown_meta_item_2.stderr
@@ -1,2 +1,6 @@
-error: invalid `--check-cfg` argument: `cfg(foo,test())` (`cfg()` arguments must be simple identifiers, `any()` or `values(...)`)
+error: invalid `--check-cfg` argument: `cfg(foo,test())`
+   |
+   = note: `test()` is invalid
+   = note: `cfg()` arguments must be simple identifiers, `any()` or `values(...)`
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.unknown_meta_item_3.stderr b/tests/ui/check-cfg/invalid-arguments.unknown_meta_item_3.stderr
index a023779b35a..a8ab9cc9d30 100644
--- a/tests/ui/check-cfg/invalid-arguments.unknown_meta_item_3.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.unknown_meta_item_3.stderr
@@ -1,2 +1,6 @@
-error: invalid `--check-cfg` argument: `cfg(foo,values(test()))` (`values()` arguments must be string literals, `none()` or `any()`)
+error: invalid `--check-cfg` argument: `cfg(foo,values(test()))`
+   |
+   = note: `test()` is invalid
+   = note: `values()` arguments must be string literals, `none()` or `any()`
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.unterminated.stderr b/tests/ui/check-cfg/invalid-arguments.unterminated.stderr
index 80161a6aa0f..150e1d66426 100644
--- a/tests/ui/check-cfg/invalid-arguments.unterminated.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.unterminated.stderr
@@ -1,2 +1,5 @@
-error: invalid `--check-cfg` argument: `cfg(` (expected `cfg(name, values("value1", "value2", ... "valueN"))`)
+error: invalid `--check-cfg` argument: `cfg(`
+   |
+   = note: expected `cfg(name, values("value1", "value2", ... "valueN"))`
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.values_any_before_ident.stderr b/tests/ui/check-cfg/invalid-arguments.values_any_before_ident.stderr
index fc93ec8fbdf..7013bb8e095 100644
--- a/tests/ui/check-cfg/invalid-arguments.values_any_before_ident.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.values_any_before_ident.stderr
@@ -1,2 +1,5 @@
-error: invalid `--check-cfg` argument: `cfg(values(any()),foo)` (`values()` cannot be specified before the names)
+error: invalid `--check-cfg` argument: `cfg(values(any()),foo)`
+   |
+   = note: `values()` cannot be specified before the names
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details
 
diff --git a/tests/ui/check-cfg/invalid-arguments.values_any_missing_values.stderr b/tests/ui/check-cfg/invalid-arguments.values_any_missing_values.stderr
index f41672fcbdb..ad1af73c690 100644
--- a/tests/ui/check-cfg/invalid-arguments.values_any_missing_values.stderr
+++ b/tests/ui/check-cfg/invalid-arguments.values_any_missing_values.stderr
@@ -1,2 +1,5 @@
-error: invalid `--check-cfg` argument: `cfg(foo,any())` (`cfg(any())` can only be provided in isolation)
+error: invalid `--check-cfg` argument: `cfg(foo,any())`
+   |
+   = note: `cfg(any())` can only be provided in isolation
+   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details