diff --git a/Makefile.am b/Makefile.am
index a4ac71b..3c77939 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -13,7 +13,7 @@ cava_SOURCES = cava.c config.c input/common.c input/fifo.c input/shmem.c \
                output/terminal_noncurses.c output/raw.c
 cava_LDFLAGS = -L/usr/local/lib -Wl,-rpath /usr/local/lib
 cava_CPPFLAGS = -DPACKAGE=\"$(PACKAGE)\" -DVERSION=\"$(VERSION)\" \
-           -D_POSIX_SOURCE -D _POSIX_C_SOURCE=200809L
+           -D_POSIX_SOURCE -D _POSIX_C_SOURCE=200809L -D_XOPEN_SOURCE_EXTENDED
 cava_CFLAGS = -std=c99 -Wall -Wextra -Wno-unused-result -Wno-maybe-uninitialized 
 
 if OSX
diff --git a/cava.c b/cava.c
index 437f75f..45ec0c3 100644
--- a/cava.c
+++ b/cava.c
@@ -1,4 +1,3 @@
-#define _XOPEN_SOURCE_EXTENDED
 #include <locale.h>
 
 #ifdef HAVE_ALLOCA_H