[Qt-creator] Add a Build for Distribution menu choice to QtCreator

[Coda Highland]

On Mon, Apr 7, 2014 at 1:17 AM, Koehne Kai <Kai.Koehne at digia.com> wrote:
>> And on the Mac, if you try
>> run the Qt app in a folder that's been macdeployqt'ed on your
>> development Mac you'll get the double Qt syndrome.
>
> I'm not into Mac too much ... is this a known issue? Is there a task for it?

It's known at least among Qt/Mac developers; it's been true for as
long as I can remember (which is to say, Qt 4.3.0, which is when I
first switched from Linux to Mac). What happens is that running "make"
after running macdeployqt doesn't actually wipe the .app bundle, it
just replaces the binary inside (and possibly replacing the
Info.plist, I'm not sure) while leaving the copies of the Qt
frameworks inside as well. The dynamic loader gets really confused by
this; I'm not sure exactly where the references get ambiguous enough
but the end result is that two copies of Qt get loaded and step on
each other's toes.

Considering it hadn't been fixed in so many years, I had just chalked
it up to "macdeployqt must be low in the support tiers" and assumed it
was something that Mac developers just needed to be aware of and work
around.

It would be simple enough to fix the problem by having the makefile
delete the app bundle in its entirety on a make. (This would also
resolve another minor cosmetic issue in the process, which is that the
app bundle's modification date doesn't change when the binary inside
gets replaced, making the timestamps in the filesystem misleading.)

/s/ Adam