Thanks for pointer. Roku can now connect properly with zlib-18.104.22.168.
For anyone trying to build under RH9, the ./configure flags I used are
–enable-sqlite –enable-flac LIBS=-lm CFLAGS=-D_GNU_SOURCE
LIBS needs this because some versions of libFLAC contain an unresolved reference to log().
CFLAGS gets rid of the 4 final implicit function declarations warnings