Han-Wen Nienhuys <hanwenn@xxxxxxxxx> writes:
> On Wed, Feb 19, 2020 at 7:10 PM Junio C Hamano <gitster@xxxxxxxxx> wrote:
>> It is OK (and indeed you're right that you cannot avoid it) to ship
>> a reasonably new snapshot as a fallback in such a case, but it still
>> is far more preferrable to avoid linking with the fallback snapshot
>> copy when a working one is available on the system, especially for a
>> widely used and established library like zlib, because we have one
>> less thing to keep up-to-date with the security patches made to the
>> upstream.
>
> what is the procedure for doing this? Do I need to write autoconf
> macros (oh no!) ?
We treat the Makefile macros listed at the top of the file as
authoritative set of knobs, so
# Define ZLIB_LACKS_UNCOMPRESS2 if your zlib is so old to lack the
# function uncompress2().
with conditional compilation/linkage based on the macro would be
minimally sufficient. Setting it automatically in ./configure is
nice-to-have but is optional.
