It's not my day ..

libpthread/linuxthreads/sysdeps/pthread/pthread.h

@@ -24,7 +24,7 @@
 #include <signal.h>
 #include <bits/pthreadtypes.h>
 #include <bits/initspin.h>
-#if defined _LIBC && ( defined IS_IN_libc && NOT_IN_libc )
+#if defined _LIBC && ( defined IS_IN_libc && defined NOT_IN_libc )
 #include <bits/uClibc_pthread.h>
 #endif