skeletal@phalanx ~/Games/crawl/crawl-ref/source $ make
CC crc32.o
In file included from crc32.c:29:
zutil.h:21:24: error: no include path in which to search for stddef.h
zutil.h:23:22: error: no include path in which to search for string.h
zutil.h:24:22: error: no include path in which to search for stdlib.h
zutil.h:38:23: error: no include path in which to search for errno.h
crc32.c:36:24: error: no include path in which to search for limits.h
make[2]: *** [crc32.o] Error 1
make[1]: *** [zlib] Error 2
make: *** [.contrib-libs] Error 2