Re: [png-mng-implement] Query about libpng release with zlib 1.2.11

[John B. <joh...@gm...>]

zlib is a separate package.  I tested 1.2.10 against I think every
currently supported libpng version and my main development system (which is
Gentoo) is currently running 1.2.11, which means that any tests I do are
against 1.2.11.  I haven't run a complete set yet, but I don't anticipate
any problems with 1.2.11.

Upgrading to 1.2.11 is possible without recompilation of libpng or anything
which uses it; this has been happening on my own system with every release.
  zlib releases are API and ABI backward compatible; you can upgrade,
however you can't downgrade (zlib doesn't offer forward compatibility in
general).

I have never tried any of the machine specific enhancements; I only run
unmodified zlib.   Building libpng with "make check" is probably a
reasonable way of validating the basic functionality of a modified zlib,
but any zlib client only uses a small fraction of the compression options
and only presents a small fraction of the possible compressed streams to
"inflate".

John Bowler
​