https://bugs.gentoo.org/918124
https://github.com/rockowitz/ddcutil/commit/4e2681a89fc5ba1ab5f909e30baf9eef0c99e5bd
diff --git a/src/cmdline/cmd_parser_goption.c b/src/cmdline/cmd_parser_goption.c
index 342d7b03..5168861f 100644
--- a/src/cmdline/cmd_parser_goption.c
+++ b/src/cmdline/cmd_parser_goption.c
@@ -1604,6 +1604,7 @@ parse_command(
       FREE(fl2_work);
    }
 
+#ifdef USE_USB
    if (ignored_vid_pid) {
       int ndx = 0;
       for (char * cur = ignored_vid_pid[ndx]; cur && ndx < 10; cur=ignored_vid_pid[++ndx]) {
@@ -1630,6 +1631,7 @@ parse_command(
       ntsa_free(ignored_vid_pid,true);
       ignored_vid_pid = NULL;
    }
+#endif
 
    if (sleep_multiplier_work) {
       float multiplier = 0.0f;