a new zlib version was release (1.2.11), and the old archives was moved, so there can not downloaded from zlib.net anymore.
The build process aborts at this point.
and zlib has bugs (see quote from zlib.net)
Version 1.2.11 has these key improvements over 1.2.10:
- Fix deflate stored bug when pulling last block from window
- Permit immediate deflateParams changes before any deflate input
Due to the bug fixes, any installations of 1.2.9 or 1.2.10 should be immediately replaced with 1.2.11.
Version 1.2.10 has these key improvements over 1.2.9:
- Fix bug in deflate_stored() for zero-length input
- Fix bug in gzwrite.c that produced corrupt gzip files