fix some FreeBSD issues
diff --git a/configs/freebsd b/configs/freebsd
index db7dd3b..447faf9 100644
--- a/configs/freebsd
+++ b/configs/freebsd
@@ -13,7 +13,7 @@
 PIC_FLAGS  = -fPIC
 
 DEFINES = -D_POSIX_SOURCE -D_POSIX_C_SOURCE=199309L -D_BSD_SOURCE -DUSE_XSHM \
-	-DHZ=100 -DHAVE_POSIX_MEMALIGN
+	-DHZ=100
 
 X11_INCLUDES = -I/usr/X11R6/include