diff --git a/config.h b/config.h
index ecb4ed4f..99915f4b 100644
--- a/config.h
+++ b/config.h
@@ -1,3 +1,4 @@
+#ifndef CONFIG_H
 /* ============================================================
  * Control compile time options.
  * ============================================================
@@ -28,5 +29,7 @@
 #define uthash_malloc(sz) mosquitto__malloc(sz)
 #define uthash_free(ptr,sz) mosquitto__free(ptr)
 
-#define _BSD_SOURCE
+#define _DEFAULT_SOURCE 1
 #define _POSIX_C_SOURCE 200809L
+
+#endif
diff --git a/src/Makefile b/src/Makefile
index ee79bd39..227f6623 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -200,7 +200,7 @@ mosquitto_passwd : mosquitto_passwd.o
 	${CROSS_COMPILE}${CC} $^ -o $@ ${LDFLAGS} $(PASSWD_LIBS)
 
 mosquitto_passwd.o : mosquitto_passwd.c
-	${CROSS_COMPILE}${CC} $(CFLAGS) ${CPPFLAGS} -c $< -o $@
+	${CROSS_COMPILE}${CC} -I.. $(CFLAGS) ${CPPFLAGS} -c $< -o $@
 
 plugin_defer.so : plugin_defer.c mosquitto_plugin.h mosquitto_broker.h mosquitto_broker_internal.h
 	${CROSS_COMPILE}${CC} -I. -I../lib -fPIC -shared $< -o $@
diff --git a/src/mosquitto.c b/src/mosquitto.c
index 590a3cb8..1829c5e8 100644
--- a/src/mosquitto.c
+++ b/src/mosquitto.c
@@ -18,7 +18,6 @@ Contributors:
 
 #ifndef WIN32
 /* For initgroups() */
-#  define _DEFAULT_SOURCE
 #  include <unistd.h>
 #  include <grp.h>
 #  include <assert.h>
diff --git a/src/mosquitto_passwd.c b/src/mosquitto_passwd.c
index 8cad3b12..1b479a4f 100644
--- a/src/mosquitto_passwd.c
+++ b/src/mosquitto_passwd.c
@@ -14,8 +14,7 @@ Contributors:
    Roger Light - initial implementation and documentation.
 */
 
-#define _POSIX_C_SOURCE 200809L
-#define _DEFAULT_SOURCE
+#include "config.h"
 
 #include <errno.h>
 #include <openssl/evp.h>