pyconfig.h defines _POSIX_C_SOURCE to 200112L, which prevents QNX's sys/types.h from defining uint_t. Samba 4 uses this type, so it fails to compile if Python.h is included first (cf. https://bugzilla.samba.org/show_bug.cgi?id=6842). The attached patch fixes this issue by defining _QNX_SOURCE.