diff --git a/diff.c b/diff.c
index f644947c82..e21af3b7ee 100644
--- a/diff.c
+++ b/diff.c
@@ -2477,6 +2477,10 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 		DIFF_OPT_SET(options, ALLOW_EXTERNAL);
 	else if (!strcmp(arg, "--no-ext-diff"))
 		DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
+	else if (!strcmp(arg, "--textconv"))
+		DIFF_OPT_SET(options, ALLOW_TEXTCONV);
+	else if (!strcmp(arg, "--no-textconv"))
+		DIFF_OPT_CLR(options, ALLOW_TEXTCONV);
 	else if (!strcmp(arg, "--ignore-submodules"))
 		DIFF_OPT_SET(options, IGNORE_SUBMODULES);