Index: binutils/gold/timer.cc
===================================================================
--- binutils.orig/gold/timer.cc
+++ binutils/gold/timer.cc
@@ -50,6 +50,9 @@ Timer::start()
 }
 
 #if HAVE_SYSCONF && defined _SC_CLK_TCK
+# if HAVE_UNISTD_H
+#  include <unistd.h>
+# endif
 # define TICKS_PER_SECOND sysconf (_SC_CLK_TCK) /* POSIX 1003.1-1996 */
 #else
 # ifdef CLK_TCK