diff --git a/src/plugins/lan/lan.c b/src/plugins/lan/lan.c
index 8010b17..14730d3 100644
--- a/src/plugins/lan/lan.c
+++ b/src/plugins/lan/lan.c
@@ -29,7 +29,7 @@
  * LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
  * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
  */
-#define _POSIX_SOURCE
+#define _GNU_SOURCE
 
 #include <stdlib.h>
 #include <stdio.h>
diff --git a/src/plugins/lanplus/lanplus.c b/src/plugins/lanplus/lanplus.c
index a815d04..490d3f5 100644
--- a/src/plugins/lanplus/lanplus.c
+++ b/src/plugins/lanplus/lanplus.c
@@ -29,7 +29,7 @@
  * LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
  * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
  */
-#define _POSIX_SOURCE
+#define _GNU_SOURCE
 
 #include <stdlib.h>
 #include <stdio.h>
diff --git a/src/plugins/serial/serial_basic.c b/src/plugins/serial/serial_basic.c
index f70fa11..fe2ebff 100644
--- a/src/plugins/serial/serial_basic.c
+++ b/src/plugins/serial/serial_basic.c
@@ -33,6 +33,7 @@
 
 /* Serial Interface, Basic Mode plugin. */
 
+#include <alloca.h>
 #include <stdio.h>
 #include <fcntl.h>
 #include <time.h>
diff --git a/src/plugins/serial/serial_terminal.c b/src/plugins/serial/serial_terminal.c
index 1bfd672..dfcc202 100644
--- a/src/plugins/serial/serial_terminal.c
+++ b/src/plugins/serial/serial_terminal.c
@@ -33,6 +33,7 @@
 
 /* Serial Interface, Terminal Mode plugin. */
 
+#include <alloca.h>
 #include <stdio.h>
 #include <fcntl.h>
 #include <unistd.h>