diff --git a/compiler/rustc_codegen_ssa/messages.ftl b/compiler/rustc_codegen_ssa/messages.ftl
index a80f6a1add099..97285b85d06d7 100644
--- a/compiler/rustc_codegen_ssa/messages.ftl
+++ b/compiler/rustc_codegen_ssa/messages.ftl
@@ -160,6 +160,8 @@ codegen_ssa_linker_file_stem = couldn't extract file stem from specified linker
 codegen_ssa_linker_not_found = linker `{$linker_path}` not found
     .note = {$error}
 
+codegen_ssa_linker_output = {$inner}
+
 codegen_ssa_linker_unsupported_modifier = `as-needed` modifier not supported for current linker
 
 codegen_ssa_linking_failed = linking with `{$linker_path}` failed: {$exit_status}
diff --git a/compiler/rustc_codegen_ssa/src/back/link.rs b/compiler/rustc_codegen_ssa/src/back/link.rs
index b29f71bfb9553..239c7d53c7e47 100644
--- a/compiler/rustc_codegen_ssa/src/back/link.rs
+++ b/compiler/rustc_codegen_ssa/src/back/link.rs
@@ -731,6 +731,14 @@ fn link_dwarf_object<'a>(
     }
 }
 
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_linker_output)]
+/// Translating this is kind of useless. We don't pass translation flags to the linker, so we'd just
+/// end up with inconsistent languages within the same diagnostic.
+struct LinkerOutput {
+    inner: String,
+}
+
 /// Create a dynamic library or executable.
 ///
 /// This will invoke the system linker/cc to create the resulting file. This links to all upstream
@@ -936,12 +944,12 @@ fn link_natively<'a>(
                 let mut output = prog.stderr.clone();
                 output.extend_from_slice(&prog.stdout);
                 let escaped_output = escape_linker_output(&output, flavor);
-                // FIXME: Add UI tests for this error.
                 let err = errors::LinkingFailed {
                     linker_path: &linker_path,
                     exit_status: prog.status,
                     command: &cmd,
                     escaped_output,
+                    verbose: sess.opts.verbose,
                 };
                 sess.dcx().emit_err(err);
                 // If MSVC's `link.exe` was expected but the return code
@@ -982,8 +990,22 @@ fn link_natively<'a>(
 
                 sess.dcx().abort_if_errors();
             }
-            info!("linker stderr:\n{}", escape_string(&prog.stderr));
-            info!("linker stdout:\n{}", escape_string(&prog.stdout));
+
+            if !prog.stderr.is_empty() {
+                // We already print `warning:` at the start of the diagnostic. Remove it from the linker output if present.
+                let stderr = escape_string(&prog.stderr);
+                debug!("original stderr: {stderr}");
+                let stderr = stderr
+                    .strip_prefix("warning: ")
+                    .unwrap_or(&stderr)
+                    .replace(": warning: ", ": ");
+                sess.dcx().emit_warn(LinkerOutput { inner: format!("linker stderr: {stderr}") });
+            }
+            if !prog.stdout.is_empty() && sess.opts.verbose {
+                sess.dcx().emit_warn(LinkerOutput {
+                    inner: format!("linker stdout: {}", escape_string(&prog.stdout)),
+                });
+            }
         }
         Err(e) => {
             let linker_not_found = e.kind() == io::ErrorKind::NotFound;
diff --git a/compiler/rustc_codegen_ssa/src/errors.rs b/compiler/rustc_codegen_ssa/src/errors.rs
index 06ea5b9e8f4ab..a39520ae03392 100644
--- a/compiler/rustc_codegen_ssa/src/errors.rs
+++ b/compiler/rustc_codegen_ssa/src/errors.rs
@@ -340,6 +340,7 @@ pub struct LinkingFailed<'a> {
     pub exit_status: ExitStatus,
     pub command: &'a Command,
     pub escaped_output: String,
+    pub verbose: bool,
 }
 
 impl<G: EmissionGuarantee> IntoDiagnostic<'_, G> for LinkingFailed<'_> {
@@ -350,7 +351,13 @@ impl<G: EmissionGuarantee> IntoDiagnostic<'_, G> for LinkingFailed<'_> {
 
         let contains_undefined_ref = self.escaped_output.contains("undefined reference to");
 
-        diag.note(format!("{:?}", self.command)).note(self.escaped_output);
+        if self.verbose {
+            diag.note(format!("{:?}", self.command));
+        } else {
+            diag.note("use `--verbose` to show all linker arguments");
+        }
+
+        diag.note(self.escaped_output);
 
         // Trying to match an error from OS linkers
         // which by now we have no way to translate.
diff --git a/compiler/rustc_macros/src/diagnostics/diagnostic_builder.rs b/compiler/rustc_macros/src/diagnostics/diagnostic_builder.rs
index 85bb9584a0575..0861e1eb24282 100644
--- a/compiler/rustc_macros/src/diagnostics/diagnostic_builder.rs
+++ b/compiler/rustc_macros/src/diagnostics/diagnostic_builder.rs
@@ -249,7 +249,10 @@ impl DiagnosticDeriveVariantBuilder {
         let mut field_binding = binding_info.binding.clone();
         field_binding.set_span(field.ty.span());
 
-        let ident = field.ident.as_ref().unwrap();
+        let Some(ident) = field.ident.as_ref() else {
+            span_err(field.span().unwrap(), "tuple structs are not supported").emit();
+            return TokenStream::new();
+        };
         let ident = format_ident!("{}", ident); // strip `r#` prefix, if present
 
         quote! {
diff --git a/compiler/rustc_macros/src/diagnostics/error.rs b/compiler/rustc_macros/src/diagnostics/error.rs
index 84b18a6202814..aba01340fd59b 100644
--- a/compiler/rustc_macros/src/diagnostics/error.rs
+++ b/compiler/rustc_macros/src/diagnostics/error.rs
@@ -55,7 +55,7 @@ fn path_to_string(path: &syn::Path) -> String {
 /// Returns an error diagnostic on span `span` with msg `msg`.
 #[must_use]
 pub(crate) fn span_err<T: Into<String>>(span: impl MultiSpan, msg: T) -> Diagnostic {
-    Diagnostic::spanned(span, Level::Error, msg)
+    Diagnostic::spanned(span, Level::Error, format!("derive(Diagnostic): {}", msg.into()))
 }
 
 /// Emit a diagnostic on span `$span` with msg `$msg` (optionally performing additional decoration
diff --git a/compiler/rustc_macros/src/diagnostics/utils.rs b/compiler/rustc_macros/src/diagnostics/utils.rs
index 4684306e23592..3c59e610f66a1 100644
--- a/compiler/rustc_macros/src/diagnostics/utils.rs
+++ b/compiler/rustc_macros/src/diagnostics/utils.rs
@@ -242,7 +242,7 @@ impl<T> SetOnce<T> for SpannedOption<T> {
                 *self = Some((value, span));
             }
             Some((_, prev_span)) => {
-                span_err(span, "specified multiple times")
+                span_err(span, "attribute specified multiple times")
                     .span_note(*prev_span, "previously specified here")
                     .emit();
             }
diff --git a/src/etc/cat-and-grep.sh b/src/etc/cat-and-grep.sh
index 238f7f5b66027..68c6993ac15ef 100755
--- a/src/etc/cat-and-grep.sh
+++ b/src/etc/cat-and-grep.sh
@@ -33,7 +33,6 @@ while getopts ':vieh' OPTION; do
     case "$OPTION" in
         v)
             INVERT=1
-            ERROR_MSG='should not be found'
             ;;
         i)
             GREPFLAGS="i$GREPFLAGS"
diff --git a/src/tools/compiletest/src/runtest.rs b/src/tools/compiletest/src/runtest.rs
index 8be4def15dedc..b073f21f907c8 100644
--- a/src/tools/compiletest/src/runtest.rs
+++ b/src/tools/compiletest/src/runtest.rs
@@ -2135,6 +2135,10 @@ impl<'test> TestCx<'test> {
         self.config.target.contains("vxworks") && !self.is_vxworks_pure_static()
     }
 
+    fn has_aux_dir(&self) -> bool {
+        !self.props.aux_builds.is_empty() || !self.props.aux_crates.is_empty()
+    }
+
     fn build_all_auxiliary(&self, rustc: &mut Command) -> PathBuf {
         let aux_dir = self.aux_output_dir_name();
 
@@ -2612,7 +2616,11 @@ impl<'test> TestCx<'test> {
         }
 
         if let LinkToAux::Yes = link_to_aux {
-            rustc.arg("-L").arg(self.aux_output_dir_name());
+            // if we pass an `-L` argument to a directory that doesn't exist,
+            // macOS ld emits warnings which disrupt the .stderr files
+            if self.has_aux_dir() {
+                rustc.arg("-L").arg(self.aux_output_dir_name());
+            }
         }
 
         rustc.args(&self.props.compile_flags);
diff --git a/tests/run-make/link-args-order/Makefile b/tests/run-make/link-args-order/Makefile
index c562cc1b396fa..0896184f81ea5 100644
--- a/tests/run-make/link-args-order/Makefile
+++ b/tests/run-make/link-args-order/Makefile
@@ -6,5 +6,5 @@ RUSTC_FLAGS = -C linker-flavor=ld -C link-arg=a -C link-args="b c" -C link-args=
 RUSTC_FLAGS_PRE = -C linker-flavor=ld -Z pre-link-arg=a -Z pre-link-args="b c" -Z pre-link-args="d e" -Z pre-link-arg=f
 
 all:
-	$(RUSTC) $(RUSTC_FLAGS) empty.rs 2>&1 | $(CGREP) '"a" "b" "c" "d" "e" "f"'
-	$(RUSTC) $(RUSTC_FLAGS_PRE) empty.rs 2>&1 | $(CGREP) '"a" "b" "c" "d" "e" "f"'
+	$(RUSTC) $(RUSTC_FLAGS) empty.rs --print=link-args | $(CGREP) '"a" "b" "c" "d" "e" "f"'
+	$(RUSTC) $(RUSTC_FLAGS_PRE) empty.rs --print=link-args | $(CGREP) '"a" "b" "c" "d" "e" "f"'
diff --git a/tests/run-make/link-dedup/Makefile b/tests/run-make/link-dedup/Makefile
index eff18ab48ab4f..ac07068c02a7f 100644
--- a/tests/run-make/link-dedup/Makefile
+++ b/tests/run-make/link-dedup/Makefile
@@ -6,7 +6,7 @@ all:
 	$(RUSTC) depa.rs
 	$(RUSTC) depb.rs
 	$(RUSTC) depc.rs
-	$(RUSTC) empty.rs --cfg bar 2>&1 | $(CGREP) '"-ltesta" "-ltestb" "-ltesta"'
-	$(RUSTC) empty.rs 2>&1 | $(CGREP) '"-ltesta"'
-	$(RUSTC) empty.rs 2>&1 | $(CGREP) -v '"-ltestb"'
-	$(RUSTC) empty.rs 2>&1 | $(CGREP) -v '"-ltesta" "-ltesta" "-ltesta"'
+	$(RUSTC) empty.rs --cfg bar --print=link-args | $(CGREP) '"-ltesta" "-ltestb" "-ltesta"'
+	$(RUSTC) empty.rs --print=link-args | $(CGREP) '"-ltesta"'
+	$(RUSTC) empty.rs --print=link-args | $(CGREP) -v '"-ltestb"'
+	$(RUSTC) empty.rs --print=link-args | $(CGREP) -v '"-ltesta" "-ltesta" "-ltesta"'
diff --git a/tests/run-make/linker-warning/Makefile b/tests/run-make/linker-warning/Makefile
new file mode 100644
index 0000000000000..ecb36aee21440
--- /dev/null
+++ b/tests/run-make/linker-warning/Makefile
@@ -0,0 +1,25 @@
+include ../tools.mk
+
+RUN_RUSTC := $(RUSTC_ORIGINAL) main.rs -o $(TMPDIR)/main -C linker=./fake-linker.sh
+
+all: succeeds_with_warnings errors linker_args
+
+succeeds_with_warnings:
+	# Run rustc with our fake linker, and make sure it shows warnings
+	$(RUN_RUSTC) -C link-arg=run_make_warn 2>&1 | $(CGREP) "warning: linker stderr: bar"
+
+	# Make sure it shows stdout, but only when --verbose is passed
+	$(RUN_RUSTC) -C link-arg=run_make_info --verbose 2>&1 | $(CGREP) "warning: linker stdout: foo"
+	$(RUN_RUSTC) -C link-arg=run_make_info 2>&1 | $(CGREP) -v "warning: linker stdout: foo"
+
+errors:
+	# Make sure we short-circuit this new path if the linker exits with an error (so the diagnostic is less verbose)
+	rm -f $(TMPDIR)/main
+	$(RUN_RUSTC) -C link-arg=run_make_error 2>&1 | $(CGREP) "note: error: baz"
+	! [ -e $(TMPDIR)/main ]
+
+linker_args:
+	# Make sure we don't show the linker args unless `--verbose` is passed
+	$(RUN_RUSTC) --verbose -C link-arg=run_make_error 2>&1 | $(CGREP) -e "PATH=.*fake-linker.sh.*run_make_error"
+	$(RUN_RUSTC) -C link-arg=run_make_error 2>&1 | $(CGREP) -v -e "PATH=.*fake-linker.sh.*run_make_error"
+
diff --git a/tests/run-make/linker-warning/fake-linker.sh b/tests/run-make/linker-warning/fake-linker.sh
new file mode 100755
index 0000000000000..ed4d472c3bfbd
--- /dev/null
+++ b/tests/run-make/linker-warning/fake-linker.sh
@@ -0,0 +1,17 @@
+#!/bin/sh
+
+code=0
+while ! [ $# = 0 ]; do
+    case "$1" in
+        run_make_info) echo "foo"
+            ;;
+        run_make_warn) echo "warning: bar" >&2
+            ;;
+        run_make_error) echo "error: baz" >&2; code=1
+            ;;
+        *) ;;   # rustc passes lots of args we don't care about
+    esac
+    shift
+done
+
+exit $code
diff --git a/tests/run-make/linker-warning/main.rs b/tests/run-make/linker-warning/main.rs
new file mode 100644
index 0000000000000..f328e4d9d04c3
--- /dev/null
+++ b/tests/run-make/linker-warning/main.rs
@@ -0,0 +1 @@
+fn main() {}
diff --git a/tests/ui-fulldeps/session-diagnostic/diagnostic-derive.stderr b/tests/ui-fulldeps/session-diagnostic/diagnostic-derive.stderr
index 67257c28b6eb0..7b03169d625f6 100644
--- a/tests/ui-fulldeps/session-diagnostic/diagnostic-derive.stderr
+++ b/tests/ui-fulldeps/session-diagnostic/diagnostic-derive.stderr
@@ -1,10 +1,10 @@
-error: unsupported type attribute for diagnostic derive enum
+error: derive(Diagnostic): unsupported type attribute for diagnostic derive enum
   --> $DIR/diagnostic-derive.rs:47:1
    |
 LL | #[diag(no_crate_example, code = E0123)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: diagnostic slug not specified
+error: derive(Diagnostic): diagnostic slug not specified
   --> $DIR/diagnostic-derive.rs:50:5
    |
 LL |     Foo,
@@ -12,7 +12,7 @@ LL |     Foo,
    |
    = help: specify the slug as the first argument to the `#[diag(...)]` attribute, such as `#[diag(hir_analysis_example_error)]`
 
-error: diagnostic slug not specified
+error: derive(Diagnostic): diagnostic slug not specified
   --> $DIR/diagnostic-derive.rs:52:5
    |
 LL |     Bar,
@@ -20,13 +20,13 @@ LL |     Bar,
    |
    = help: specify the slug as the first argument to the `#[diag(...)]` attribute, such as `#[diag(hir_analysis_example_error)]`
 
-error: `#[nonsense(...)]` is not a valid attribute
+error: derive(Diagnostic): `#[nonsense(...)]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:63:1
    |
 LL | #[nonsense(no_crate_example, code = E0123)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: diagnostic slug not specified
+error: derive(Diagnostic): diagnostic slug not specified
   --> $DIR/diagnostic-derive.rs:63:1
    |
 LL | / #[nonsense(no_crate_example, code = E0123)]
@@ -38,7 +38,7 @@ LL | | struct InvalidStructAttr {}
    |
    = help: specify the slug as the first argument to the `#[diag(...)]` attribute, such as `#[diag(hir_analysis_example_error)]`
 
-error: diagnostic slug not specified
+error: derive(Diagnostic): diagnostic slug not specified
   --> $DIR/diagnostic-derive.rs:70:1
    |
 LL | / #[diag(code = E0123)]
@@ -48,13 +48,13 @@ LL | | struct InvalidLitNestedAttr {}
    |
    = help: specify the slug as the first argument to the `#[diag(...)]` attribute, such as `#[diag(hir_analysis_example_error)]`
 
-error: diagnostic slug must be the first argument
+error: derive(Diagnostic): diagnostic slug must be the first argument
   --> $DIR/diagnostic-derive.rs:80:16
    |
 LL | #[diag(nonsense("foo"), code = E0123, slug = "foo")]
    |                ^
 
-error: diagnostic slug not specified
+error: derive(Diagnostic): diagnostic slug not specified
   --> $DIR/diagnostic-derive.rs:80:1
    |
 LL | / #[diag(nonsense("foo"), code = E0123, slug = "foo")]
@@ -65,7 +65,7 @@ LL | | struct InvalidNestedStructAttr1 {}
    |
    = help: specify the slug as the first argument to the `#[diag(...)]` attribute, such as `#[diag(hir_analysis_example_error)]`
 
-error: unknown argument
+error: derive(Diagnostic): unknown argument
   --> $DIR/diagnostic-derive.rs:86:8
    |
 LL | #[diag(nonsense = "...", code = E0123, slug = "foo")]
@@ -73,7 +73,7 @@ LL | #[diag(nonsense = "...", code = E0123, slug = "foo")]
    |
    = note: only the `code` parameter is valid after the slug
 
-error: diagnostic slug not specified
+error: derive(Diagnostic): diagnostic slug not specified
   --> $DIR/diagnostic-derive.rs:86:1
    |
 LL | / #[diag(nonsense = "...", code = E0123, slug = "foo")]
@@ -84,7 +84,7 @@ LL | | struct InvalidNestedStructAttr2 {}
    |
    = help: specify the slug as the first argument to the `#[diag(...)]` attribute, such as `#[diag(hir_analysis_example_error)]`
 
-error: unknown argument
+error: derive(Diagnostic): unknown argument
   --> $DIR/diagnostic-derive.rs:92:8
    |
 LL | #[diag(nonsense = 4, code = E0123, slug = "foo")]
@@ -92,7 +92,7 @@ LL | #[diag(nonsense = 4, code = E0123, slug = "foo")]
    |
    = note: only the `code` parameter is valid after the slug
 
-error: diagnostic slug not specified
+error: derive(Diagnostic): diagnostic slug not specified
   --> $DIR/diagnostic-derive.rs:92:1
    |
 LL | / #[diag(nonsense = 4, code = E0123, slug = "foo")]
@@ -103,7 +103,7 @@ LL | | struct InvalidNestedStructAttr3 {}
    |
    = help: specify the slug as the first argument to the `#[diag(...)]` attribute, such as `#[diag(hir_analysis_example_error)]`
 
-error: unknown argument
+error: derive(Diagnostic): unknown argument
   --> $DIR/diagnostic-derive.rs:98:40
    |
 LL | #[diag(no_crate_example, code = E0123, slug = "foo")]
@@ -111,13 +111,13 @@ LL | #[diag(no_crate_example, code = E0123, slug = "foo")]
    |
    = note: only the `code` parameter is valid after the slug
 
-error: `#[suggestion = ...]` is not a valid attribute
+error: derive(Diagnostic): `#[suggestion = ...]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:105:5
    |
 LL |     #[suggestion = "bar"]
    |     ^^^^^^^^^^^^^^^^^^^^^
 
-error: specified multiple times
+error: derive(Diagnostic): attribute specified multiple times
   --> $DIR/diagnostic-derive.rs:112:8
    |
 LL | #[diag(no_crate_example, code = E0456)]
@@ -129,7 +129,7 @@ note: previously specified here
 LL | #[diag(no_crate_example, code = E0123)]
    |        ^^^^^^^^^^^^^^^^
 
-error: specified multiple times
+error: derive(Diagnostic): attribute specified multiple times
   --> $DIR/diagnostic-derive.rs:112:26
    |
 LL | #[diag(no_crate_example, code = E0456)]
@@ -141,7 +141,7 @@ note: previously specified here
 LL | #[diag(no_crate_example, code = E0123)]
    |                          ^^^^
 
-error: specified multiple times
+error: derive(Diagnostic): attribute specified multiple times
   --> $DIR/diagnostic-derive.rs:118:40
    |
 LL | #[diag(no_crate_example, code = E0123, code = E0456)]
@@ -153,13 +153,13 @@ note: previously specified here
 LL | #[diag(no_crate_example, code = E0123, code = E0456)]
    |                          ^^^^
 
-error: diagnostic slug must be the first argument
+error: derive(Diagnostic): diagnostic slug must be the first argument
   --> $DIR/diagnostic-derive.rs:123:43
    |
 LL | #[diag(no_crate_example, no_crate::example, code = E0123)]
    |                                           ^
 
-error: diagnostic slug not specified
+error: derive(Diagnostic): diagnostic slug not specified
   --> $DIR/diagnostic-derive.rs:128:1
    |
 LL | struct KindNotProvided {}
@@ -167,7 +167,7 @@ LL | struct KindNotProvided {}
    |
    = help: specify the slug as the first argument to the `#[diag(...)]` attribute, such as `#[diag(hir_analysis_example_error)]`
 
-error: diagnostic slug not specified
+error: derive(Diagnostic): diagnostic slug not specified
   --> $DIR/diagnostic-derive.rs:131:1
    |
 LL | / #[diag(code = E0123)]
@@ -177,25 +177,25 @@ LL | | struct SlugNotProvided {}
    |
    = help: specify the slug as the first argument to the `#[diag(...)]` attribute, such as `#[diag(hir_analysis_example_error)]`
 
-error: the `#[primary_span]` attribute can only be applied to fields of type `Span` or `MultiSpan`
+error: derive(Diagnostic): the `#[primary_span]` attribute can only be applied to fields of type `Span` or `MultiSpan`
   --> $DIR/diagnostic-derive.rs:142:5
    |
 LL |     #[primary_span]
    |     ^^^^^^^^^^^^^^^
 
-error: `#[nonsense]` is not a valid attribute
+error: derive(Diagnostic): `#[nonsense]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:150:5
    |
 LL |     #[nonsense]
    |     ^^^^^^^^^^^
 
-error: the `#[label(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
+error: derive(Diagnostic): the `#[label(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
   --> $DIR/diagnostic-derive.rs:167:5
    |
 LL |     #[label(no_crate_label)]
    |     ^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: `name` doesn't refer to a field on this type
+error: derive(Diagnostic): `name` doesn't refer to a field on this type
   --> $DIR/diagnostic-derive.rs:175:46
    |
 LL |     #[suggestion(no_crate_suggestion, code = "{name}")]
@@ -219,19 +219,19 @@ LL | #[derive(Diagnostic)]
    = note: if you intended to print `}`, you can escape it using `}}`
    = note: this error originates in the derive macro `Diagnostic` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: the `#[label(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
+error: derive(Diagnostic): the `#[label(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
   --> $DIR/diagnostic-derive.rs:210:5
    |
 LL |     #[label(no_crate_label)]
    |     ^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: suggestion without `code = "..."`
+error: derive(Diagnostic): suggestion without `code = "..."`
   --> $DIR/diagnostic-derive.rs:229:5
    |
 LL |     #[suggestion(no_crate_suggestion)]
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: invalid nested attribute
+error: derive(Diagnostic): invalid nested attribute
   --> $DIR/diagnostic-derive.rs:237:18
    |
 LL |     #[suggestion(nonsense = "bar")]
@@ -239,13 +239,13 @@ LL |     #[suggestion(nonsense = "bar")]
    |
    = help: only `no_span`, `style`, `code` and `applicability` are valid nested attributes
 
-error: suggestion without `code = "..."`
+error: derive(Diagnostic): suggestion without `code = "..."`
   --> $DIR/diagnostic-derive.rs:237:5
    |
 LL |     #[suggestion(nonsense = "bar")]
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: invalid nested attribute
+error: derive(Diagnostic): invalid nested attribute
   --> $DIR/diagnostic-derive.rs:246:18
    |
 LL |     #[suggestion(msg = "bar")]
@@ -253,13 +253,13 @@ LL |     #[suggestion(msg = "bar")]
    |
    = help: only `no_span`, `style`, `code` and `applicability` are valid nested attributes
 
-error: suggestion without `code = "..."`
+error: derive(Diagnostic): suggestion without `code = "..."`
   --> $DIR/diagnostic-derive.rs:246:5
    |
 LL |     #[suggestion(msg = "bar")]
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: wrong field type for suggestion
+error: derive(Diagnostic): wrong field type for suggestion
   --> $DIR/diagnostic-derive.rs:269:5
    |
 LL | /     #[suggestion(no_crate_suggestion, code = "This is suggested code")]
@@ -269,7 +269,7 @@ LL | |     suggestion: Applicability,
    |
    = help: `#[suggestion(...)]` should be applied to fields of type `Span` or `(Span, Applicability)`
 
-error: specified multiple times
+error: derive(Diagnostic): attribute specified multiple times
   --> $DIR/diagnostic-derive.rs:285:24
    |
 LL |     suggestion: (Span, Span, Applicability),
@@ -281,7 +281,7 @@ note: previously specified here
 LL |     suggestion: (Span, Span, Applicability),
    |                  ^^^^
 
-error: specified multiple times
+error: derive(Diagnostic): attribute specified multiple times
   --> $DIR/diagnostic-derive.rs:293:33
    |
 LL |     suggestion: (Applicability, Applicability, Span),
@@ -293,13 +293,13 @@ note: previously specified here
 LL |     suggestion: (Applicability, Applicability, Span),
    |                  ^^^^^^^^^^^^^
 
-error: `#[label = ...]` is not a valid attribute
+error: derive(Diagnostic): `#[label = ...]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:300:5
    |
 LL |     #[label = "bar"]
    |     ^^^^^^^^^^^^^^^^
 
-error: specified multiple times
+error: derive(Diagnostic): attribute specified multiple times
   --> $DIR/diagnostic-derive.rs:451:5
    |
 LL |     #[suggestion(no_crate_suggestion, code = "...", applicability = "maybe-incorrect")]
@@ -311,37 +311,37 @@ note: previously specified here
 LL |     suggestion: (Span, Applicability),
    |                        ^^^^^^^^^^^^^
 
-error: invalid applicability
+error: derive(Diagnostic): invalid applicability
   --> $DIR/diagnostic-derive.rs:459:69
    |
 LL |     #[suggestion(no_crate_suggestion, code = "...", applicability = "batman")]
    |                                                                     ^^^^^^^^
 
-error: the `#[help(...)]` attribute can only be applied to fields of type `Span`, `MultiSpan`, `bool` or `()`
+error: derive(Diagnostic): the `#[help(...)]` attribute can only be applied to fields of type `Span`, `MultiSpan`, `bool` or `()`
   --> $DIR/diagnostic-derive.rs:526:5
    |
 LL |     #[help(no_crate_help)]
    |     ^^^^^^^^^^^^^^^^^^^^^^
 
-error: a diagnostic slug must be the first argument to the attribute
+error: derive(Diagnostic): a diagnostic slug must be the first argument to the attribute
   --> $DIR/diagnostic-derive.rs:535:32
    |
 LL |     #[label(no_crate_label, foo)]
    |                                ^
 
-error: only `no_span` is a valid nested attribute
+error: derive(Diagnostic): only `no_span` is a valid nested attribute
   --> $DIR/diagnostic-derive.rs:543:29
    |
 LL |     #[label(no_crate_label, foo = "...")]
    |                             ^^^
 
-error: only `no_span` is a valid nested attribute
+error: derive(Diagnostic): only `no_span` is a valid nested attribute
   --> $DIR/diagnostic-derive.rs:551:29
    |
 LL |     #[label(no_crate_label, foo("..."))]
    |                             ^^^
 
-error: `#[primary_span]` is not a valid attribute
+error: derive(Diagnostic): `#[primary_span]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:563:5
    |
 LL |     #[primary_span]
@@ -349,13 +349,13 @@ LL |     #[primary_span]
    |
    = help: the `primary_span` field attribute is not valid for lint diagnostics
 
-error: `#[error(...)]` is not a valid attribute
+error: derive(Diagnostic): `#[error(...)]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:583:1
    |
 LL | #[error(no_crate_example, code = E0123)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: diagnostic slug not specified
+error: derive(Diagnostic): diagnostic slug not specified
   --> $DIR/diagnostic-derive.rs:583:1
    |
 LL | / #[error(no_crate_example, code = E0123)]
@@ -367,13 +367,13 @@ LL | | struct ErrorAttribute {}
    |
    = help: specify the slug as the first argument to the `#[diag(...)]` attribute, such as `#[diag(hir_analysis_example_error)]`
 
-error: `#[warn_(...)]` is not a valid attribute
+error: derive(Diagnostic): `#[warn_(...)]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:590:1
    |
 LL | #[warn_(no_crate_example, code = E0123)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: diagnostic slug not specified
+error: derive(Diagnostic): diagnostic slug not specified
   --> $DIR/diagnostic-derive.rs:590:1
    |
 LL | / #[warn_(no_crate_example, code = E0123)]
@@ -385,13 +385,13 @@ LL | | struct WarnAttribute {}
    |
    = help: specify the slug as the first argument to the `#[diag(...)]` attribute, such as `#[diag(hir_analysis_example_error)]`
 
-error: `#[lint(...)]` is not a valid attribute
+error: derive(Diagnostic): `#[lint(...)]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:597:1
    |
 LL | #[lint(no_crate_example, code = E0123)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: diagnostic slug not specified
+error: derive(Diagnostic): diagnostic slug not specified
   --> $DIR/diagnostic-derive.rs:597:1
    |
 LL | / #[lint(no_crate_example, code = E0123)]
@@ -403,13 +403,13 @@ LL | | struct LintAttributeOnSessionDiag {}
    |
    = help: specify the slug as the first argument to the `#[diag(...)]` attribute, such as `#[diag(hir_analysis_example_error)]`
 
-error: `#[lint(...)]` is not a valid attribute
+error: derive(Diagnostic): `#[lint(...)]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:604:1
    |
 LL | #[lint(no_crate_example, code = E0123)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: `#[lint(...)]` is not a valid attribute
+error: derive(Diagnostic): `#[lint(...)]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:604:1
    |
 LL | #[lint(no_crate_example, code = E0123)]
@@ -417,7 +417,7 @@ LL | #[lint(no_crate_example, code = E0123)]
    |
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
-error: diagnostic slug not specified
+error: derive(Diagnostic): diagnostic slug not specified
   --> $DIR/diagnostic-derive.rs:604:1
    |
 LL | / #[lint(no_crate_example, code = E0123)]
@@ -430,7 +430,7 @@ LL | | struct LintAttributeOnLintDiag {}
    |
    = help: specify the slug as the first argument to the attribute, such as `#[diag(compiletest_example)]`
 
-error: specified multiple times
+error: derive(Diagnostic): attribute specified multiple times
   --> $DIR/diagnostic-derive.rs:614:53
    |
 LL |     #[suggestion(no_crate_suggestion, code = "...", code = ",,,")]
@@ -442,7 +442,7 @@ note: previously specified here
 LL |     #[suggestion(no_crate_suggestion, code = "...", code = ",,,")]
    |                                       ^^^^
 
-error: wrong types for suggestion
+error: derive(Diagnostic): wrong types for suggestion
   --> $DIR/diagnostic-derive.rs:623:24
    |
 LL |     suggestion: (Span, usize),
@@ -450,7 +450,7 @@ LL |     suggestion: (Span, usize),
    |
    = help: `#[suggestion(...)]` on a tuple field must be applied to fields of type `(Span, Applicability)`
 
-error: wrong types for suggestion
+error: derive(Diagnostic): wrong types for suggestion
   --> $DIR/diagnostic-derive.rs:631:17
    |
 LL |     suggestion: (Span,),
@@ -458,13 +458,13 @@ LL |     suggestion: (Span,),
    |
    = help: `#[suggestion(...)]` on a tuple field must be applied to fields of type `(Span, Applicability)`
 
-error: suggestion without `code = "..."`
+error: derive(Diagnostic): suggestion without `code = "..."`
   --> $DIR/diagnostic-derive.rs:638:5
    |
 LL |     #[suggestion(no_crate_suggestion)]
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: `#[multipart_suggestion(...)]` is not a valid attribute
+error: derive(Diagnostic): `#[multipart_suggestion(...)]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:645:1
    |
 LL | #[multipart_suggestion(no_crate_suggestion)]
@@ -472,7 +472,7 @@ LL | #[multipart_suggestion(no_crate_suggestion)]
    |
    = help: consider creating a `Subdiagnostic` instead
 
-error: `#[multipart_suggestion(...)]` is not a valid attribute
+error: derive(Diagnostic): `#[multipart_suggestion(...)]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:648:1
    |
 LL | #[multipart_suggestion()]
@@ -480,7 +480,7 @@ LL | #[multipart_suggestion()]
    |
    = help: consider creating a `Subdiagnostic` instead
 
-error: `#[multipart_suggestion(...)]` is not a valid attribute
+error: derive(Diagnostic): `#[multipart_suggestion(...)]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:652:5
    |
 LL |     #[multipart_suggestion(no_crate_suggestion)]
@@ -488,7 +488,7 @@ LL |     #[multipart_suggestion(no_crate_suggestion)]
    |
    = help: consider creating a `Subdiagnostic` instead
 
-error: `#[suggestion(...)]` is not a valid attribute
+error: derive(Diagnostic): `#[suggestion(...)]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:660:1
    |
 LL | #[suggestion(no_crate_suggestion, code = "...")]
@@ -496,7 +496,7 @@ LL | #[suggestion(no_crate_suggestion, code = "...")]
    |
    = help: `#[label]` and `#[suggestion]` can only be applied to fields
 
-error: `#[label]` is not a valid attribute
+error: derive(Diagnostic): `#[label]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:669:1
    |
 LL | #[label]
@@ -504,31 +504,31 @@ LL | #[label]
    |
    = help: `#[label]` and `#[suggestion]` can only be applied to fields
 
-error: `eager` is the only supported nested attribute for `subdiagnostic`
+error: derive(Diagnostic): `eager` is the only supported nested attribute for `subdiagnostic`
   --> $DIR/diagnostic-derive.rs:703:7
    |
 LL |     #[subdiagnostic(bad)]
    |       ^^^^^^^^^^^^^^^^^^
 
-error: `#[subdiagnostic = ...]` is not a valid attribute
+error: derive(Diagnostic): `#[subdiagnostic = ...]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:711:5
    |
 LL |     #[subdiagnostic = "bad"]
    |     ^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: `eager` is the only supported nested attribute for `subdiagnostic`
+error: derive(Diagnostic): `eager` is the only supported nested attribute for `subdiagnostic`
   --> $DIR/diagnostic-derive.rs:719:7
    |
 LL |     #[subdiagnostic(bad, bad)]
    |       ^^^^^^^^^^^^^^^^^^^^^^^
 
-error: `eager` is the only supported nested attribute for `subdiagnostic`
+error: derive(Diagnostic): `eager` is the only supported nested attribute for `subdiagnostic`
   --> $DIR/diagnostic-derive.rs:727:7
    |
 LL |     #[subdiagnostic("bad")]
    |       ^^^^^^^^^^^^^^^^^^^^
 
-error: `#[subdiagnostic(...)]` is not a valid attribute
+error: derive(Diagnostic): `#[subdiagnostic(...)]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:735:5
    |
 LL |     #[subdiagnostic(eager)]
@@ -536,19 +536,19 @@ LL |     #[subdiagnostic(eager)]
    |
    = help: eager subdiagnostics are not supported on lints
 
-error: expected at least one string literal for `code(...)`
+error: derive(Diagnostic): expected at least one string literal for `code(...)`
   --> $DIR/diagnostic-derive.rs:793:23
    |
 LL |     #[suggestion(code())]
    |                       ^
 
-error: `code(...)` must contain only string literals
+error: derive(Diagnostic): `code(...)` must contain only string literals
   --> $DIR/diagnostic-derive.rs:801:23
    |
 LL |     #[suggestion(code(foo))]
    |                       ^^^
 
-error: `#[suggestion(...)]` is not a valid attribute
+error: derive(Diagnostic): `#[suggestion(...)]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:825:5
    |
 LL |     #[suggestion(no_crate_suggestion, code = "")]
diff --git a/tests/ui-fulldeps/session-diagnostic/enforce_slug_naming.stderr b/tests/ui-fulldeps/session-diagnostic/enforce_slug_naming.stderr
index eda24a555f848..25b1ae9ab2211 100644
--- a/tests/ui-fulldeps/session-diagnostic/enforce_slug_naming.stderr
+++ b/tests/ui-fulldeps/session-diagnostic/enforce_slug_naming.stderr
@@ -1,4 +1,4 @@
-error: diagnostic slug and crate name do not match
+error: derive(Diagnostic): diagnostic slug and crate name do not match
   --> $DIR/enforce_slug_naming.rs:22:8
    |
 LL | #[diag(compiletest_example, code = 0123)]
diff --git a/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.stderr b/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.stderr
index 80bee3bd6e6c3..ffc3fcfa2425a 100644
--- a/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.stderr
+++ b/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.stderr
@@ -1,4 +1,4 @@
-error: label without `#[primary_span]` field
+error: derive(Diagnostic): label without `#[primary_span]` field
   --> $DIR/subdiagnostic-derive.rs:51:1
    |
 LL | / #[label(no_crate_example)]
@@ -8,127 +8,127 @@ LL | |     var: String,
 LL | | }
    | |_^
 
-error: diagnostic slug must be first argument of a `#[label(...)]` attribute
+error: derive(Diagnostic): diagnostic slug must be first argument of a `#[label(...)]` attribute
   --> $DIR/subdiagnostic-derive.rs:58:1
    |
 LL | #[label]
    | ^^^^^^^^
 
-error: `#[foo]` is not a valid attribute
+error: derive(Diagnostic): `#[foo]` is not a valid attribute
   --> $DIR/subdiagnostic-derive.rs:67:1
    |
 LL | #[foo]
    | ^^^^^^
 
-error: `#[label = ...]` is not a valid attribute
+error: derive(Diagnostic): `#[label = ...]` is not a valid attribute
   --> $DIR/subdiagnostic-derive.rs:77:1
    |
 LL | #[label = "..."]
    | ^^^^^^^^^^^^^^^^
 
-error: only `no_span` is a valid nested attribute
+error: derive(Diagnostic): only `no_span` is a valid nested attribute
   --> $DIR/subdiagnostic-derive.rs:86:9
    |
 LL | #[label(bug = "...")]
    |         ^^^
 
-error: diagnostic slug must be first argument of a `#[label(...)]` attribute
+error: derive(Diagnostic): diagnostic slug must be first argument of a `#[label(...)]` attribute
   --> $DIR/subdiagnostic-derive.rs:86:1
    |
 LL | #[label(bug = "...")]
    | ^^^^^^^^^^^^^^^^^^^^^
 
-error: only `no_span` is a valid nested attribute
+error: derive(Diagnostic): only `no_span` is a valid nested attribute
   --> $DIR/subdiagnostic-derive.rs:106:9
    |
 LL | #[label(slug = 4)]
    |         ^^^^
 
-error: diagnostic slug must be first argument of a `#[label(...)]` attribute
+error: derive(Diagnostic): diagnostic slug must be first argument of a `#[label(...)]` attribute
   --> $DIR/subdiagnostic-derive.rs:106:1
    |
 LL | #[label(slug = 4)]
    | ^^^^^^^^^^^^^^^^^^
 
-error: only `no_span` is a valid nested attribute
+error: derive(Diagnostic): only `no_span` is a valid nested attribute
   --> $DIR/subdiagnostic-derive.rs:116:9
    |
 LL | #[label(slug("..."))]
    |         ^^^^
 
-error: diagnostic slug must be first argument of a `#[label(...)]` attribute
+error: derive(Diagnostic): diagnostic slug must be first argument of a `#[label(...)]` attribute
   --> $DIR/subdiagnostic-derive.rs:116:1
    |
 LL | #[label(slug("..."))]
    | ^^^^^^^^^^^^^^^^^^^^^
 
-error: diagnostic slug must be first argument of a `#[label(...)]` attribute
+error: derive(Diagnostic): diagnostic slug must be first argument of a `#[label(...)]` attribute
   --> $DIR/subdiagnostic-derive.rs:136:1
    |
 LL | #[label()]
    | ^^^^^^^^^^
 
-error: only `no_span` is a valid nested attribute
+error: derive(Diagnostic): only `no_span` is a valid nested attribute
   --> $DIR/subdiagnostic-derive.rs:145:27
    |
 LL | #[label(no_crate_example, code = "...")]
    |                           ^^^^
 
-error: only `no_span` is a valid nested attribute
+error: derive(Diagnostic): only `no_span` is a valid nested attribute
   --> $DIR/subdiagnostic-derive.rs:154:27
    |
 LL | #[label(no_crate_example, applicability = "machine-applicable")]
    |                           ^^^^^^^^^^^^^
 
-error: unsupported type attribute for subdiagnostic enum
+error: derive(Diagnostic): unsupported type attribute for subdiagnostic enum
   --> $DIR/subdiagnostic-derive.rs:163:1
    |
 LL | #[foo]
    | ^^^^^^
 
-error: `#[bar]` is not a valid attribute
+error: derive(Diagnostic): `#[bar]` is not a valid attribute
   --> $DIR/subdiagnostic-derive.rs:177:5
    |
 LL |     #[bar]
    |     ^^^^^^
 
-error: `#[bar = ...]` is not a valid attribute
+error: derive(Diagnostic): `#[bar = ...]` is not a valid attribute
   --> $DIR/subdiagnostic-derive.rs:189:5
    |
 LL |     #[bar = "..."]
    |     ^^^^^^^^^^^^^^
 
-error: `#[bar = ...]` is not a valid attribute
+error: derive(Diagnostic): `#[bar = ...]` is not a valid attribute
   --> $DIR/subdiagnostic-derive.rs:201:5
    |
 LL |     #[bar = 4]
    |     ^^^^^^^^^^
 
-error: `#[bar(...)]` is not a valid attribute
+error: derive(Diagnostic): `#[bar(...)]` is not a valid attribute
   --> $DIR/subdiagnostic-derive.rs:213:5
    |
 LL |     #[bar("...")]
    |     ^^^^^^^^^^^^^
 
-error: only `no_span` is a valid nested attribute
+error: derive(Diagnostic): only `no_span` is a valid nested attribute
   --> $DIR/subdiagnostic-derive.rs:225:13
    |
 LL |     #[label(code = "...")]
    |             ^^^^
 
-error: diagnostic slug must be first argument of a `#[label(...)]` attribute
+error: derive(Diagnostic): diagnostic slug must be first argument of a `#[label(...)]` attribute
   --> $DIR/subdiagnostic-derive.rs:225:5
    |
 LL |     #[label(code = "...")]
    |     ^^^^^^^^^^^^^^^^^^^^^^
 
-error: the `#[primary_span]` attribute can only be applied to fields of type `Span` or `MultiSpan`
+error: derive(Diagnostic): the `#[primary_span]` attribute can only be applied to fields of type `Span` or `MultiSpan`
   --> $DIR/subdiagnostic-derive.rs:254:5
    |
 LL |     #[primary_span]
    |     ^^^^^^^^^^^^^^^
 
-error: label without `#[primary_span]` field
+error: derive(Diagnostic): label without `#[primary_span]` field
   --> $DIR/subdiagnostic-derive.rs:251:1
    |
 LL | / #[label(no_crate_example)]
@@ -140,13 +140,13 @@ LL | |     span: String,
 LL | | }
    | |_^
 
-error: `#[applicability]` is only valid on suggestions
+error: derive(Diagnostic): `#[applicability]` is only valid on suggestions
   --> $DIR/subdiagnostic-derive.rs:264:5
    |
 LL |     #[applicability]
    |     ^^^^^^^^^^^^^^^^
 
-error: `#[bar]` is not a valid attribute
+error: derive(Diagnostic): `#[bar]` is not a valid attribute
   --> $DIR/subdiagnostic-derive.rs:274:5
    |
 LL |     #[bar]
@@ -154,13 +154,13 @@ LL |     #[bar]
    |
    = help: only `primary_span`, `applicability` and `skip_arg` are valid field attributes
 
-error: `#[bar = ...]` is not a valid attribute
+error: derive(Diagnostic): `#[bar = ...]` is not a valid attribute
   --> $DIR/subdiagnostic-derive.rs:285:5
    |
 LL |     #[bar = "..."]
    |     ^^^^^^^^^^^^^^
 
-error: `#[bar(...)]` is not a valid attribute
+error: derive(Diagnostic): `#[bar(...)]` is not a valid attribute
   --> $DIR/subdiagnostic-derive.rs:296:5
    |
 LL |     #[bar("...")]
@@ -168,13 +168,13 @@ LL |     #[bar("...")]
    |
    = help: only `primary_span`, `applicability` and `skip_arg` are valid field attributes
 
-error: a diagnostic slug must be the first argument to the attribute
+error: derive(Diagnostic): a diagnostic slug must be the first argument to the attribute
   --> $DIR/subdiagnostic-derive.rs:328:44
    |
 LL | #[label(no_crate_example, no_crate::example)]
    |                                            ^
 
-error: specified multiple times
+error: derive(Diagnostic): attribute specified multiple times
   --> $DIR/subdiagnostic-derive.rs:341:5
    |
 LL |     #[primary_span]
@@ -186,13 +186,13 @@ note: previously specified here
 LL |     #[primary_span]
    |     ^^^^^^^^^^^^^^^
 
-error: subdiagnostic kind not specified
+error: derive(Diagnostic): subdiagnostic kind not specified
   --> $DIR/subdiagnostic-derive.rs:347:8
    |
 LL | struct AG {
    |        ^^
 
-error: specified multiple times
+error: derive(Diagnostic): attribute specified multiple times
   --> $DIR/subdiagnostic-derive.rs:384:46
    |
 LL | #[suggestion(no_crate_example, code = "...", code = "...")]
@@ -204,7 +204,7 @@ note: previously specified here
 LL | #[suggestion(no_crate_example, code = "...", code = "...")]
    |                                ^^^^
 
-error: specified multiple times
+error: derive(Diagnostic): attribute specified multiple times
   --> $DIR/subdiagnostic-derive.rs:402:5
    |
 LL |     #[applicability]
@@ -216,25 +216,25 @@ note: previously specified here
 LL |     #[applicability]
    |     ^^^^^^^^^^^^^^^^
 
-error: the `#[applicability]` attribute can only be applied to fields of type `Applicability`
+error: derive(Diagnostic): the `#[applicability]` attribute can only be applied to fields of type `Applicability`
   --> $DIR/subdiagnostic-derive.rs:412:5
    |
 LL |     #[applicability]
    |     ^^^^^^^^^^^^^^^^
 
-error: suggestion without `code = "..."`
+error: derive(Diagnostic): suggestion without `code = "..."`
   --> $DIR/subdiagnostic-derive.rs:425:1
    |
 LL | #[suggestion(no_crate_example)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: invalid applicability
+error: derive(Diagnostic): invalid applicability
   --> $DIR/subdiagnostic-derive.rs:435:62
    |
 LL | #[suggestion(no_crate_example, code = "...", applicability = "foo")]
    |                                                              ^^^^^
 
-error: suggestion without `#[primary_span]` field
+error: derive(Diagnostic): suggestion without `#[primary_span]` field
   --> $DIR/subdiagnostic-derive.rs:453:1
    |
 LL | / #[suggestion(no_crate_example, code = "...")]
@@ -244,25 +244,25 @@ LL | |     var: String,
 LL | | }
    | |_^
 
-error: unsupported type attribute for subdiagnostic enum
+error: derive(Diagnostic): unsupported type attribute for subdiagnostic enum
   --> $DIR/subdiagnostic-derive.rs:467:1
    |
 LL | #[label]
    | ^^^^^^^^
 
-error: `var` doesn't refer to a field on this type
+error: derive(Diagnostic): `var` doesn't refer to a field on this type
   --> $DIR/subdiagnostic-derive.rs:487:39
    |
 LL | #[suggestion(no_crate_example, code = "{var}", applicability = "machine-applicable")]
    |                                       ^^^^^^^
 
-error: `var` doesn't refer to a field on this type
+error: derive(Diagnostic): `var` doesn't refer to a field on this type
   --> $DIR/subdiagnostic-derive.rs:506:43
    |
 LL |     #[suggestion(no_crate_example, code = "{var}", applicability = "machine-applicable")]
    |                                           ^^^^^^^
 
-error: `#[suggestion_part]` is not a valid attribute
+error: derive(Diagnostic): `#[suggestion_part]` is not a valid attribute
   --> $DIR/subdiagnostic-derive.rs:529:5
    |
 LL |     #[suggestion_part]
@@ -270,7 +270,7 @@ LL |     #[suggestion_part]
    |
    = help: `#[suggestion_part(...)]` is only valid in multipart suggestions, use `#[primary_span]` instead
 
-error: `#[suggestion_part(...)]` is not a valid attribute
+error: derive(Diagnostic): `#[suggestion_part(...)]` is not a valid attribute
   --> $DIR/subdiagnostic-derive.rs:532:5
    |
 LL |     #[suggestion_part(code = "...")]
@@ -278,7 +278,7 @@ LL |     #[suggestion_part(code = "...")]
    |
    = help: `#[suggestion_part(...)]` is only valid in multipart suggestions
 
-error: suggestion without `#[primary_span]` field
+error: derive(Diagnostic): suggestion without `#[primary_span]` field
   --> $DIR/subdiagnostic-derive.rs:526:1
    |
 LL | / #[suggestion(no_crate_example, code = "...")]
@@ -290,7 +290,7 @@ LL | |     var: String,
 LL | | }
    | |_^
 
-error: invalid nested attribute
+error: derive(Diagnostic): invalid nested attribute
   --> $DIR/subdiagnostic-derive.rs:541:42
    |
 LL | #[multipart_suggestion(no_crate_example, code = "...", applicability = "machine-applicable")]
@@ -298,7 +298,7 @@ LL | #[multipart_suggestion(no_crate_example, code = "...", applicability = "mac
    |
    = help: only `no_span`, `style` and `applicability` are valid nested attributes
 
-error: multipart suggestion without any `#[suggestion_part(...)]` fields
+error: derive(Diagnostic): multipart suggestion without any `#[suggestion_part(...)]` fields
   --> $DIR/subdiagnostic-derive.rs:541:1
    |
 LL | / #[multipart_suggestion(no_crate_example, code = "...", applicability = "machine-applicable")]
@@ -309,19 +309,19 @@ LL | |     var: String,
 LL | | }
    | |_^
 
-error: `#[suggestion_part(...)]` attribute without `code = "..."`
+error: derive(Diagnostic): `#[suggestion_part(...)]` attribute without `code = "..."`
   --> $DIR/subdiagnostic-derive.rs:551:5
    |
 LL |     #[suggestion_part]
    |     ^^^^^^^^^^^^^^^^^^
 
-error: `#[suggestion_part(...)]` attribute without `code = "..."`
+error: derive(Diagnostic): `#[suggestion_part(...)]` attribute without `code = "..."`
   --> $DIR/subdiagnostic-derive.rs:559:5
    |
 LL |     #[suggestion_part()]
    |     ^^^^^^^^^^^^^^^^^^^^
 
-error: `#[primary_span]` is not a valid attribute
+error: derive(Diagnostic): `#[primary_span]` is not a valid attribute
   --> $DIR/subdiagnostic-derive.rs:568:5
    |
 LL |     #[primary_span]
@@ -329,7 +329,7 @@ LL |     #[primary_span]
    |
    = help: multipart suggestions use one or more `#[suggestion_part]`s rather than one `#[primary_span]`
 
-error: multipart suggestion without any `#[suggestion_part(...)]` fields
+error: derive(Diagnostic): multipart suggestion without any `#[suggestion_part(...)]` fields
   --> $DIR/subdiagnostic-derive.rs:565:1
    |
 LL | / #[multipart_suggestion(no_crate_example)]
@@ -341,37 +341,37 @@ LL | |     span: Span,
 LL | | }
    | |_^
 
-error: `#[suggestion_part(...)]` attribute without `code = "..."`
+error: derive(Diagnostic): `#[suggestion_part(...)]` attribute without `code = "..."`
   --> $DIR/subdiagnostic-derive.rs:576:5
    |
 LL |     #[suggestion_part]
    |     ^^^^^^^^^^^^^^^^^^
 
-error: `#[suggestion_part(...)]` attribute without `code = "..."`
+error: derive(Diagnostic): `#[suggestion_part(...)]` attribute without `code = "..."`
   --> $DIR/subdiagnostic-derive.rs:579:5
    |
 LL |     #[suggestion_part()]
    |     ^^^^^^^^^^^^^^^^^^^^
 
-error: `code` is the only valid nested attribute
+error: derive(Diagnostic): `code` is the only valid nested attribute
   --> $DIR/subdiagnostic-derive.rs:582:23
    |
 LL |     #[suggestion_part(foo = "bar")]
    |                       ^^^
 
-error: the `#[suggestion_part(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
+error: derive(Diagnostic): the `#[suggestion_part(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
   --> $DIR/subdiagnostic-derive.rs:587:5
    |
 LL |     #[suggestion_part(code = "...")]
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: the `#[suggestion_part(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
+error: derive(Diagnostic): the `#[suggestion_part(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
   --> $DIR/subdiagnostic-derive.rs:590:5
    |
 LL |     #[suggestion_part()]
    |     ^^^^^^^^^^^^^^^^^^^^
 
-error: specified multiple times
+error: derive(Diagnostic): attribute specified multiple times
   --> $DIR/subdiagnostic-derive.rs:598:37
    |
 LL |     #[suggestion_part(code = "...", code = ",,,")]
@@ -383,37 +383,37 @@ note: previously specified here
 LL |     #[suggestion_part(code = "...", code = ",,,")]
    |                       ^^^^
 
-error: `#[applicability]` has no effect if all `#[suggestion]`/`#[multipart_suggestion]` attributes have a static `applicability = "..."`
+error: derive(Diagnostic): `#[applicability]` has no effect if all `#[suggestion]`/`#[multipart_suggestion]` attributes have a static `applicability = "..."`
   --> $DIR/subdiagnostic-derive.rs:627:5
    |
 LL |     #[applicability]
    |     ^^^^^^^^^^^^^^^^
 
-error: expected exactly one string literal for `code = ...`
+error: derive(Diagnostic): expected exactly one string literal for `code = ...`
   --> $DIR/subdiagnostic-derive.rs:675:34
    |
 LL |     #[suggestion_part(code("foo"))]
    |                                  ^
 
-error: expected exactly one string literal for `code = ...`
+error: derive(Diagnostic): expected exactly one string literal for `code = ...`
   --> $DIR/subdiagnostic-derive.rs:686:41
    |
 LL |     #[suggestion_part(code("foo", "bar"))]
    |                                         ^
 
-error: expected exactly one string literal for `code = ...`
+error: derive(Diagnostic): expected exactly one string literal for `code = ...`
   --> $DIR/subdiagnostic-derive.rs:697:30
    |
 LL |     #[suggestion_part(code(3))]
    |                              ^
 
-error: expected exactly one string literal for `code = ...`
+error: derive(Diagnostic): expected exactly one string literal for `code = ...`
   --> $DIR/subdiagnostic-derive.rs:708:29
    |
 LL |     #[suggestion_part(code())]
    |                             ^
 
-error: specified multiple times
+error: derive(Diagnostic): attribute specified multiple times
   --> $DIR/subdiagnostic-derive.rs:763:1
    |
 LL | #[suggestion(no_crate_example, code = "", style = "hidden", style = "normal")]
@@ -425,7 +425,7 @@ note: previously specified here
 LL | #[suggestion(no_crate_example, code = "", style = "hidden", style = "normal")]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: `#[suggestion_hidden(...)]` is not a valid attribute
+error: derive(Diagnostic): `#[suggestion_hidden(...)]` is not a valid attribute
   --> $DIR/subdiagnostic-derive.rs:772:1
    |
 LL | #[suggestion_hidden(no_crate_example, code = "")]
@@ -433,7 +433,7 @@ LL | #[suggestion_hidden(no_crate_example, code = "")]
    |
    = help: Use `#[suggestion(..., style = "hidden")]` instead
 
-error: `#[suggestion_hidden(...)]` is not a valid attribute
+error: derive(Diagnostic): `#[suggestion_hidden(...)]` is not a valid attribute
   --> $DIR/subdiagnostic-derive.rs:780:1
    |
 LL | #[suggestion_hidden(no_crate_example, code = "", style = "normal")]
@@ -441,7 +441,7 @@ LL | #[suggestion_hidden(no_crate_example, code = "", style = "normal")]
    |
    = help: Use `#[suggestion(..., style = "hidden")]` instead
 
-error: invalid suggestion style
+error: derive(Diagnostic): invalid suggestion style
   --> $DIR/subdiagnostic-derive.rs:788:51
    |
 LL | #[suggestion(no_crate_example, code = "", style = "foo")]
@@ -449,25 +449,25 @@ LL | #[suggestion(no_crate_example, code = "", style = "foo")]
    |
    = help: valid styles are `normal`, `short`, `hidden`, `verbose` and `tool-only`
 
-error: expected `= "xxx"`
+error: derive(Diagnostic): expected `= "xxx"`
   --> $DIR/subdiagnostic-derive.rs:796:49
    |
 LL | #[suggestion(no_crate_example, code = "", style = 42)]
    |                                                 ^
 
-error: a diagnostic slug must be the first argument to the attribute
+error: derive(Diagnostic): a diagnostic slug must be the first argument to the attribute
   --> $DIR/subdiagnostic-derive.rs:804:48
    |
 LL | #[suggestion(no_crate_example, code = "", style)]
    |                                                ^
 
-error: expected `= "xxx"`
+error: derive(Diagnostic): expected `= "xxx"`
   --> $DIR/subdiagnostic-derive.rs:812:48
    |
 LL | #[suggestion(no_crate_example, code = "", style("foo"))]
    |                                                ^
 
-error: `#[primary_span]` is not a valid attribute
+error: derive(Diagnostic): `#[primary_span]` is not a valid attribute
   --> $DIR/subdiagnostic-derive.rs:825:5
    |
 LL |     #[primary_span]
@@ -476,7 +476,7 @@ LL |     #[primary_span]
    = note: there must be exactly one primary span
    = help: to create a suggestion with multiple spans, use `#[multipart_suggestion]` instead
 
-error: suggestion without `#[primary_span]` field
+error: derive(Diagnostic): suggestion without `#[primary_span]` field
   --> $DIR/subdiagnostic-derive.rs:822:1
    |
 LL | / #[suggestion(no_crate_example, code = "")]