ERROR: sizeof(size_t) doesn't match GLIB_SIZEOF_SIZE_T.

cont build from last 2.6 rc4

~/Downloads/qemu-2.6.0-rc4$ ./configure 

ERROR: sizeof(size_t) doesn't match GLIB_SIZEOF_SIZE_T.
       You probably need to set PKG_CONFIG_LIBDIR
       to point to the right pkg-config files for your
       build target

Os Ubuntu Mate 16.04 PPC64