Re: [PATCH] Add target-zlib to top-level configure, use zlib from libphobos

[Matthias Klose <doko@ubuntu.com>]

On 12.02.19 21:54, Iain Buclaw wrote:
> On Tue, 12 Feb 2019 at 10:40, Richard Biener <richard.guenther@gmail.com> wrote:
>>
>> On Sat, Feb 9, 2019 at 10:37 AM Iain Buclaw <ibuclaw@gdcproject.org> wrote:
>>>
>>> On Mon, 28 Jan 2019 at 13:10, Richard Biener <richard.guenther@gmail.com> wrote:
>>>>
>>>> On Mon, Jan 21, 2019 at 7:35 PM Iain Buclaw <ibuclaw@gdcproject.org> wrote:
>>>>>
>>>>> Hi,
>>>>>
>>>>> Following on from the last, this adds target-zlib to target_libraries
>>>>> and updates libphobos build scripts to link to libz_convenience.a.
>>>>> The D front-end already has target-zlib in d/config-lang.in.
>>>>>
>>>>> Is the top-level part OK?  I considered disabling target-zlib if
>>>>> libphobos is not being built, but decided against unless it's
>>>>> requested.
>>>>
>>>> Hmm, you overload --with-system-zlib to apply to both host and target
>>>> (I guess it already applied to build), not sure if that's really desired?
>>>> I suppose libphobos is the first target library linking against zlib?
>>>>
>>>
>>> Originally, libgcj linked to zlib.
>>>
>>>> You are also falling back to in-tree zlib if --with-system-zlib was
>>>> specified but no zlib was found - I guess for cross builds that
>>>> will easily get not noticed...  The toplevel --with-system-zlib makes
>>>> it much harder and simply fails.
>>>>
>>>
>>> OK, so keep --with-target-system-zlib to distinguish between the two?
>>
>> Yes, and fail if specificed but not found.
>>
> 
> Updated patch.  Checked that it correctly fails when
> --with-target-system-zlib and zlib missing.

For the GC enabled libobjc I added an --enable-objc-gc=auto to fall-back to the
in-tree library when no system library is found. Could you do the same for zlib?
There might be some multilib variants missing in distros.

Matthias