diff --git a/usr.bin/gcore/elfcore.c b/usr.bin/gcore/elfcore.c
index 1d57db90840c..bcbbad6a5483 100644
--- a/usr.bin/gcore/elfcore.c
+++ b/usr.bin/gcore/elfcore.c
@@ -27,7 +27,6 @@
  */
 
 #include <sys/param.h>
-#include <sys/lock.h>
 #include <sys/procfs.h>
 #include <machine/elf.h>
 #include <vm/vm_param.h>