diff --git a/usr.bin/kdump/kdump.c b/usr.bin/kdump/kdump.c
--- a/usr.bin/kdump/kdump.c
+++ b/usr.bin/kdump/kdump.c
@@ -937,7 +937,8 @@
 				narg -= 2;
 				break;
 			case SYS_wait4:
-				print_number(ip, narg, c);
+				*ip = (pid_t)*ip;
+				print_decimal_number(ip, narg, c);
 				print_number(ip, narg, c);
 				putchar(',');
 				print_mask_arg0(sysdecode_wait4_options, *ip);
@@ -950,7 +951,7 @@
 				c = ',';
 				ip++;
 				narg--;
-				print_number64(first, ip, narg, c);
+				print_decimal_number64(first, ip, narg, c);
 				print_number(ip, narg, c);
 				putchar(',');
 				print_mask_arg(sysdecode_wait6_options, *ip);