diff --git a/lib/asn1/asn1_gen.c b/lib/asn1/asn1_gen.c
index e184e28a8..fc02ea793 100644
--- a/lib/asn1/asn1_gen.c
+++ b/lib/asn1/asn1_gen.c
@@ -166,11 +166,11 @@ usage(int code)
 int
 main(int argc, char **argv)
 {
-    int optind = 0;
+    int optidx = 0;
 
     setprogname (argv[0]);
 
-    if(getarg(args, num_args, argc, argv, &optind))
+    if(getarg(args, num_args, argc, argv, &optidx))
 	usage(1);
     if(help_flag)
 	usage(0);
@@ -178,8 +178,8 @@ main(int argc, char **argv)
 	print_version(NULL);
 	exit(0);
     }
-    argv += optind;
-    argc -= optind;
+    argv += optidx;
+    argc -= optidx;
     if (argc != 1)
 	usage (1);