UPDATE - to support diag introduced in PR rust-lang#100765

Author: JhonnyBillM

compiler/rustc_symbol_mangling/src/errors.rs

@@ -4,31 +4,31 @@ use rustc_macros::SessionDiagnostic;
 use rustc_span::Span;
 
 #[derive(SessionDiagnostic)]
-#[error(symbol_mangling::invalid_symbol_name)]
+#[diag(symbol_mangling::invalid_symbol_name)]
 pub struct InvalidSymbolName {
     #[primary_span]
     pub span: Span,
     pub mangled_formatted: String,
 }
 
 #[derive(SessionDiagnostic)]
-#[error(symbol_mangling::invalid_trait_item)]
+#[diag(symbol_mangling::invalid_trait_item)]
 pub struct InvalidTraitItem {
     #[primary_span]
     pub span: Span,
     pub demangling_formatted: String,
 }
 
 #[derive(SessionDiagnostic)]
-#[error(symbol_mangling::alt_invalid_trait_item)]
+#[diag(symbol_mangling::alt_invalid_trait_item)]
 pub struct AltInvalidTraitItem {
     #[primary_span]
     pub span: Span,
     pub alt_demangling_formatted: String,
 }
 
 #[derive(SessionDiagnostic)]
-#[error(symbol_mangling::invalid_def_path)]
+#[diag(symbol_mangling::invalid_def_path)]
 pub struct InvalidDefPath {
     #[primary_span]
     pub span: Span,