pkg-config CFLAGS/LIBS ignored in GLIB 2.26.0 build

[Mike <puffy taco gmail com>]

I am attempting to cross-compile GLIB 2.26.0, and it is complaining
that it cannot find zlib.h.  The configure script is properly finding
the correct CFLAGS to include the path to zlib.h using pkg-config, and
is storing them in ZLIB_CFLAGS.  Now, the problem is that this
variable is not used in any Makefile, only set.  Therefore, these
flags are not properly being passed to the compiler.  Am I missing
something?

Thanks,
Mike