zlib configuration : system vs. bundled

[Alan Bateman]

On 14/05/2019 15:58, Baesken, Matthias wrote:
> :
>
> On the other OS platforms, in case a zlib is found on the system :
>
>    if test "x${ZLIB_FOUND}" != "xyes"; then
>      # If we don't find any system...set default to bundled
>      DEFAULT_ZLIB=bundled
>    fi
>
> we use it from the system .
> Wouldn't  it be more  consistent to  have  zlib=bundled as well as default for the other UNIX platforms + MacOSX ?
> ( people who wish to use  the system zlib still can configure it )
>
> Otherwise we often run into using old zlib installations at build time which might not be desired.
>
It was a deliberate change in JDK 9 to use the system zlib if possible. 
Windows is the outlier. If you through the archives of core-libs-dev 
then you should find several discussions about this, I think the most 
recent was in 2016, subject line "JDK-8031767 Support system or 
alternative implementations of zlib".

-Alan