Re: RFC: docker for CI

[David Kastrup]

Jonas Hahnfeld via Discussions on LilyPond development
<address@hidden> writes:

> Am Freitag, den 07.02.2020, 13:21 +0100 schrieb Han-Wen Nienhuys:
>> 
>> Considerations
>> ==============
>> 
>> * Because the build happens inside a container, we can test multiple
>>   builds. We could build against guile 1.8 and 2.2 at the same time,
>>   for example
>
> I don't agree that we need containers for this, you can easily set
> environment variables to make configure pick up the version you want to
> use.

I use stuff like

./configure GUILE_CONFIG=/usr/local/tmp/guile-1.8/bin/guile-config 
GUILE=/usr/bin/guile

all the time.

>> * Because the "build binary" step reuses CCache results, it can
>>   complete quickly.
>
> Maybe I don't fully understand the proposal, but:
>  * if we only build the release image for every "official" tag, it will
> not provide quicker builds - especially towards the end of a cycle when
> many changes have accumulated.
>  * if instead we build images for every commit, then incremental
> building of a provided patch will be fast(er) (_if_ it doesn't touch
> any header file). But what's then the point of using ccache, we can
> just trigger a full build?

Full builds are slower.  But I really don't trust our dependencies all
too much, and for example Clang builds don't get a working set of
dependencies anyway (which is sort of curious since it is the modular
Clang that should be able to parse for them easily).

-- 
David Kastrup