Index: head/lib/libc/resolv/res_init.c
===================================================================
--- head/lib/libc/resolv/res_init.c
+++ head/lib/libc/resolv/res_init.c
@@ -116,7 +116,9 @@
 
 /*% Options.  Should all be left alone. */
 #define RESOLVSORT
-#define DEBUG
+#ifndef	DEBUG
+#define	DEBUG
+#endif
 
 #ifdef SOLARIS2
 #include <sys/systeminfo.h>
Index: head/lib/libc/resolv/res_mkquery.c
===================================================================
--- head/lib/libc/resolv/res_mkquery.c
+++ head/lib/libc/resolv/res_mkquery.c
@@ -83,7 +83,9 @@
 #include "port_after.h"
 
 /* Options.  Leave them on. */
-#define DEBUG
+#ifndef	DEBUG
+#define	DEBUG
+#endif
 
 extern const char *_res_opcodes[];
 
Index: head/lib/libc/resolv/res_mkupdate.c
===================================================================
--- head/lib/libc/resolv/res_mkupdate.c
+++ head/lib/libc/resolv/res_mkupdate.c
@@ -54,7 +54,9 @@
 #include "port_after.h"
 
 /* Options.  Leave them on. */
-#define DEBUG
+#ifndef	DEBUG
+#define	DEBUG
+#endif
 #define MAXPORT 1024
 
 static int getnum_str(u_char **, u_char *);
Index: head/lib/libc/resolv/res_query.c
===================================================================
--- head/lib/libc/resolv/res_query.c
+++ head/lib/libc/resolv/res_query.c
@@ -88,7 +88,9 @@
 #include "port_after.h"
 
 /* Options.  Leave them on. */
-#define DEBUG
+#ifndef	DEBUG
+#define	DEBUG
+#endif
 
 #if PACKETSZ > 1024
 #define MAXPACKET	PACKETSZ
Index: head/lib/libc/resolv/res_send.c
===================================================================
--- head/lib/libc/resolv/res_send.c
+++ head/lib/libc/resolv/res_send.c
@@ -119,7 +119,9 @@
 #include "un-namespace.h"
 
 /* Options.  Leave them on. */
-#define DEBUG
+#ifndef	DEBUG
+#define	DEBUG
+#endif
 #include "res_debug.h"
 #include "res_private.h"