diff --git a/man8/ld.so.8 b/man8/ld.so.8
index 7763d9070..0dae83926 100644
--- a/man8/ld.so.8
+++ b/man8/ld.so.8
@@ -380,10 +380,17 @@ Show auxiliary array passed up from the kernel.
 For security reasons, since glibc 2.3.5,
 .B LD_SHOW_AUXV
 is ignored for set-user-ID/set-group-ID binaries.
-.\" FIXME
-.\" Document LD_TRACE_PRELINKING (e.g.: LD_TRACE_PRELINKING=libx1.so ./prog)
-.\"	Available since glibc 2.3
-.\"	Also enables DL_DEBUG_PRELINK
+.TP
+.B LD_TRACE_PRELINKING
+(glibc since 2.4)
+Trace prelinking of the object whose name is assigned to
+this environment variable.
+(Use
+.BR ldd (1)
+to get a list of the objects that might be traced.)
+If the object name is not recognized,
+.\" (This is what seems to happen, from experimenting)
+then all prelinking activity is traced.
 .TP
 .B LD_USE_LOAD_BIAS
 .\" http://sources.redhat.com/ml/libc-hacker/2003-11/msg00127.html