glcpp: Initialize error state.
diff --git a/glcpp/glcpp-parse.y b/glcpp/glcpp-parse.y
index c314e95..2ce8632 100644
--- a/glcpp/glcpp-parse.y
+++ b/glcpp/glcpp-parse.y
@@ -950,6 +950,7 @@
 
 	parser->output = talloc_strdup(parser, "");
 	parser->info_log = talloc_strdup(parser, "");
+	parser->error = 0;
 
 	return parser;
 }