diff --git a/gtk/gtkcssparser.c b/gtk/gtkcssparser.c
index b6fae87686..8d3912ede1 100644
--- a/gtk/gtkcssparser.c
+++ b/gtk/gtkcssparser.c
@@ -142,6 +142,23 @@ _gtk_css_parser_error (GtkCssParser *parser,
   _gtk_css_parser_take_error (parser, error);
 }
 
+void
+_gtk_css_parser_error_full (GtkCssParser        *parser,
+                            GtkCssProviderError  code,
+                            const char          *format,
+                            ...)
+{
+  GError *error;
+
+  va_list args;
+
+  va_start (args, format);
+  error = g_error_new_valist (GTK_CSS_PROVIDER_ERROR,
+                              code, format, args);
+  va_end (args);
+
+  _gtk_css_parser_take_error (parser, error);
+}
 static gboolean
 gtk_css_parser_new_line (GtkCssParser *parser)
 {
diff --git a/gtk/gtkcssparserprivate.h b/gtk/gtkcssparserprivate.h
index ba36d6ea9c..dd9e228e20 100644
--- a/gtk/gtkcssparserprivate.h
+++ b/gtk/gtkcssparserprivate.h
@@ -19,6 +19,7 @@
 #define __GTK_CSS_PARSER_PRIVATE_H__
 
 #include "gtk/gtkcsstypesprivate.h"
+#include <gtk/gtkcssprovider.h>
 #include <gtk/gtksymboliccolor.h>
 
 G_BEGIN_DECLS
@@ -48,6 +49,10 @@ void            _gtk_css_parser_take_error        (GtkCssParser          *parser
 void            _gtk_css_parser_error             (GtkCssParser          *parser,
                                                    const char            *format,
                                                     ...) G_GNUC_PRINTF (2, 3);
+void            _gtk_css_parser_error_full        (GtkCssParser          *parser,
+                                                   GtkCssProviderError    code,
+                                                   const char            *format,
+                                                    ...) G_GNUC_PRINTF (3, 4);
 
 guint           _gtk_css_parser_get_line          (GtkCssParser          *parser);
 guint           _gtk_css_parser_get_position      (GtkCssParser          *parser);