Qt5 switching qreal from float to double on arm*

[Loïc Minier]

On Thu, Nov 07, 2013, Lisandro Damián Nicanor Pérez Meyer wrote:
> - We don't know yet what other distros are going to do.

IMO we shouldn't have distro-specific patching for this kind of stuff;
it seems to commonly impact apps (which should be using qreal instead of
assuming qreal is double) way too commonly, and we want binaries to be
compatible between distros, so diverging from upstream seems a really
bad idea.

> - If we decide to do the change in Qt5, it will be *without* soname bump. Yes, 
> I know many of you will think of this as **ugly**, but so far means 3 binNMUs 
> per arch. Now if this is not acceptable, then no change will be made, because 
> I won't change Qt5's SONAME.

Well, it's kind of ugly but we could take this hit once and go through a
binary transition with a package name change, or some kind of other
transition trick.  Not pretty and breaks compat between binaries built
against old lib and new lib, but things in Debian will be ok.

Also, as you note, not too many things are using Qt5 yet; might be a
good time to get this right.

Likely something the release team would be able to advise on, I would
guess.

> I really don't know, it was already there when I started using Qt back in 
> Qt3's final days ;-)

Eh ok; if you get the chance to ask, that would be helpful to know when
porting apps; perhaps it's something to bring up upstream in "issues
faced by distros" kind of chatters  :-)

-- 
Loïc Minier