glcpp: Introduce new glcpp_error function.
diff --git a/glcpp/glcpp.h b/glcpp/glcpp.h
index 2d4c847..45bbff3 100644
--- a/glcpp/glcpp.h
+++ b/glcpp/glcpp.h
@@ -165,6 +165,9 @@
 void
 glcpp_parser_destroy (glcpp_parser_t *parser);
 
+void
+glcpp_error (YYLTYPE *locp, glcpp_parser_t *parser, const char *fmt, ...);
+
 /* Generated by glcpp-lex.l to glcpp-lex.c */
 
 int