Re: Add --with-llvm to the development snapshot build of Pg11

Re: Andres Freund 2018-04-02 <20180402182419(dot)5bbevkbbscsjvw3s(at)alap3(dot)anarazel(dot)de>
> > (The worse bloat is actually in postgresql-server-dev-11 which now
> > also needs to depend on clang and llvm-dev.)
>
> I'm a lot less concerned about that, personally. If you're installing
> server headers you're already depending on a lot of other libraries, and
> you're not that likely to do so on production systems.

Actually not that many - the libs are rather small (at least before
the dependency on libicu-dev arrived), and more importantly, during
the libssl-dev/libssl1.0-dev unentangling during the stretch freeze, I
removed all the dependencies from libpq-dev so it doesn't
automatically pull in ssl, kerberos, icu, etc. (Which doesn't seem to
be a problem for most users, there have been only very few
complaints.)

libllvm4.0 needs 50 MB installed, postgresql-11 needs another 50 MB on
top of it.

postgresql-server-dev-11 is much fatter. Given postgresql-11 is
already installed (including libllvm4.0):

Die folgenden NEUEN Pakete werden installiert:
binfmt-support clang clang-4.0 libclang-common-4.0-dev libclang1-4.0 libffi-dev libjsoncpp1
libobjc-7-dev libobjc4 libtinfo-dev llvm llvm-4.0 llvm-4.0-dev llvm-4.0-runtime llvm-dev
llvm-runtime postgresql-server-dev-11
0 aktualisiert, 17 neu installiert, 0 zu entfernen und 4 nicht aktualisiert.
Es müssen 42,4 MB an Archiven heruntergeladen werden.
Nach dieser Operation werden 255 MB Plattenplatz zusätzlich benutzt.

(I'm not too much concerned either.)

> Hm, I guess there'd be build failures of extensions if llvm-$ver and
> clang aren't installed, because bitcode files will be automatically
> built. I don't think there's a dependency on llvm-$ver-dev however?

Afaict all extensions are (or were) failing now, yes. I have to
investigate llvm-dev vs. llvm, thanks for the pointer.

> Sizewise, the bitcode files for postgres and its extensions aren't that
> small. ~10MB compressed or such?

The Installed-Size of postgresql-11 went up from 22 MB to 42 MB, or
the like. The bigger increase is in number of files, unpacking the
.deb takes much longer now. Of 1517 files in postgresql-11, 968 are
bitcode files.

Christoph