diff --git a/newlib/ChangeLog b/newlib/ChangeLog
index 4f0afc92d..10880bb9f 100644
--- a/newlib/ChangeLog
+++ b/newlib/ChangeLog
@@ -1,3 +1,8 @@
+2003-10-14  Christopher Faylor  <cgf@redhat.com>
+
+	* libc/time/clock.c: Clarify documentation of return value when no
+	measurement is available.
+
 2003-09-29  Ian Lance Taylor  <ian@wasabisystems.com>
 
 	* libm/configure.in: Check libm_machine_dir, not machine_dir.
diff --git a/newlib/libc/time/clock.c b/newlib/libc/time/clock.c
index b15915d6a..64cf438fb 100644
--- a/newlib/libc/time/clock.c
+++ b/newlib/libc/time/clock.c
@@ -41,7 +41,7 @@ into seconds, divide by the macro <<CLOCKS_PER_SEC>>.
 RETURNS
 The amount of processor time used so far by your program, in units
 defined by the machine-dependent macro <<CLOCKS_PER_SEC>>.  If no
-measurement is available, the result is <<-1>>.
+measurement is available, the result is (clock_t)<<-1>>.
 
 PORTABILITY
 ANSI C requires <<clock>> and <<CLOCKS_PER_SEC>>.