[Paraview] QT5/libxcb on RHEL5

[Ben Boeckel]

On Wed, Sep 23, 2015 at 16:46:51 +0000, Angelini, Richard C (Rick) CIV USARMY RDECOM ARL (US) wrote:
> I’m doing some test build of PV 4.4.0, and if I try to build using
> QT5, I need to have access to the libxcb libraries.    It doesn’t look
> like there’s an RPM for this for RHEL5 .    Can the Superbuild script
> be tweaked to pick up the sources for this dependent library and build
> it if it can’t find it on the system?     Otherwise, at least on
> RHEL5, I’ll need to download/build outside of the Superbuild?

Qt5 needs a newer libxcb than is shipped on some of these older distros
(1.2? I'd have to double check). For example, Debian Etch'n'half (yes,
Debian 4) which we use to build the current binaries cannot build it.
And a newer libxcb needs a newer X than is availble tooi and that
certainly isn't going to be added to the superbuild :) . I would expect
RHEL5 to have similar problems (RHEL6 would be better).

Besides that, there is a known bug in Qt5 which makes user interaction
painful on X. Basically, mouse events aren't collapsed, so every mouse
event has a render call in between. It's basically unusable. There is a
patch which got merged in for 5.6.0, but that hasn't had a release yet.

--Ben