merge from gcc

libiberty/clock.c

@@ -22,6 +22,18 @@ the resulting executable to be covered by the GNU General Public License.
 This exception does not however invalidate any other reasons why
 the executable file might be covered by the GNU General Public License. */
 
+/*
+
+@deftypefn Supplemental long clock ()
+
+Returns an approximation of the CPU time used by the process as a
+@code{clock_t}; divide this number by @samp{CLOCKS_PER_SEC} to get the
+number of seconds used.
+
+@end deftypefn
+
+*/
+
 #include "config.h"
 
 #ifdef HAVE_GETRUSAGE