--- tests/bn_isqrt.c.orig	Sun Nov 27 10:48:32 2022
+++ tests/bn_isqrt.c	Sun Nov 27 10:48:49 2022
@@ -303,6 +303,7 @@ main(int argc, char *argv[])
 	int ch;
 	int failed = 0, print = 0;
 
+#ifndef _MSC_VER
 	while ((ch = getopt(argc, argv, "C")) != -1) {
 		switch (ch) {
 		case 'C':
@@ -313,6 +314,7 @@ main(int argc, char *argv[])
 			break;
 		}
 	}
+#endif
 
 	if (print)
 		return check_tables(1);