diff --git a/src/wmlib/audio/audio_alsa.c b/src/wmlib/audio/audio_alsa.c
--- a/src/wmlib/audio/audio_alsa.c
+++ b/src/wmlib/audio/audio_alsa.c
@@ -30,6 +30,9 @@
 
 #ifdef HAVE_ALSA
 
+#define _BSD_SOURCE /* strdup */
+#define _DEFAULT_SOURCE /* stop glibc whining about the previous line */
+
 #include <alsa/asoundlib.h>
 
 static char *device = NULL;
diff --git a/src/wmlib/cdrom.c b/src/wmlib/cdrom.c
--- a/src/wmlib/cdrom.c
+++ b/src/wmlib/cdrom.c
@@ -24,6 +24,9 @@
  * platform- or drive-dependent code here.
  */
 
+#define _BSD_SOURCE /* strdup */
+#define _DEFAULT_SOURCE /* stop glibc whining about the previous line */
+
 #include "include/wm_config.h"
 #include "include/wm_struct.h"
 #include "include/wm_cddb.h"
diff --git a/src/wmlib/wm_helpers.c b/src/wmlib/wm_helpers.c
--- a/src/wmlib/wm_helpers.c
+++ b/src/wmlib/wm_helpers.c
@@ -23,6 +23,9 @@
  *
  */
 
+#define _BSD_SOURCE /* strdup, timerclear */
+#define _DEFAULT_SOURCE /* stop glibc whining about the previous line */
+
 #include <stdio.h>
 #include <string.h>
 #include <stdlib.h>