Import error creating import library

compiler/rustc_codegen_llvm/src/errors.rs

@@ -1,5 +1,6 @@
 use rustc_errors::fluent;
 use rustc_errors::DiagnosticBuilder;
+use rustc_macros::SessionDiagnostic;
 use rustc_session::SessionDiagnostic;
 
 pub(crate) enum UnknownCTargetFeature<'a> {
@@ -34,3 +35,10 @@ impl SessionDiagnostic<'_, ()> for UnknownCTargetFeature<'_> {
         }
     }
 }
+
+#[derive(SessionDiagnostic)]
+#[diag(codegen_llvm::error_creating_import_library)]
+pub(crate) struct ErrorCreatingImportLibrary<'a> {
+    pub lib_name: &'a str,
+    pub error: String,
+}