diff --git a/sbin/ldconfig/ldconfig.8 b/sbin/ldconfig/ldconfig.8
index 3734d24ff152..7c378472f859 100644
--- a/sbin/ldconfig/ldconfig.8
+++ b/sbin/ldconfig/ldconfig.8
@@ -29,7 +29,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd January 6, 2018
+.Dd March 17, 2020
 .Dt LDCONFIG 8
 .Os
 .Sh NAME
@@ -111,6 +111,8 @@ Generate the hints for 32-bit ABI shared libraries
 on 64-bit systems that support running 32-bit binaries.
 .It Fl aout
 Generate the hints for a.out format shared libraries.
+This option is deprecated and is not present in
+.Fx 13 .
 .It Fl elf
 Generate the hints for ELF format shared libraries.
 .It Fl R
diff --git a/sbin/ldconfig/ldconfig.c b/sbin/ldconfig/ldconfig.c
index d8318b67815d..ca51b670a34c 100644
--- a/sbin/ldconfig/ldconfig.c
+++ b/sbin/ldconfig/ldconfig.c
@@ -118,6 +118,7 @@ main(int argc, char **argv)
 
 	while (argc > 1) {
 		if (strcmp(argv[1], "-aout") == 0) {
+			warnx("aout support is deprecated");
 			is_aout = 1;
 			argc--;
 			argv++;