[Interest] Fwd: QtCompositor API : is it bit-rotting ?

[Thiago Macieira]

Em sex 14 fev 2014, às 12:32:28, Rutledge Shawn escreveu:
> If it works, then the next question is, can we change Qt so that xcb is
> completely optional at runtime, even if it exists and configure has found
> it, if you are using the wayland plugin; while at the same time the same Qt
> library will happily use X11 if you use that plugin.  That way you could
> switch between wayland and X11 desktops (or stack them up) without needing
> two different Qt builds.  I don't know if that's possible, just seems that
> it should be.

Qt5Gui does not directly link to xcb:

$ objdump -p libQt5Gui.so | grep NEEDED
  NEEDED               libQt5Core.so.5
  NEEDED               libpthread.so.0
  NEEDED               libpng12.so.0
  NEEDED               libz.so.1
  NEEDED               libGLESv2.so.2
  NEEDED               libstdc++.so.6
  NEEDED               libm.so.6
  NEEDED               libc.so.6

If you see it in ldd, it's because of an indirect link. Most likely the GLESv2 
library. 

In any case, that doesn't happen here either. But libEGL *does* link to xcb:

$ objdump -p /usr/lib64/libEGL.so.1 | grep NEEDED
  NEEDED               libX11-xcb.so.1
  NEEDED               libX11.so.6
  NEEDED               libxcb-dri2.so.0
  NEEDED               libxcb-xfixes.so.0
  NEEDED               libxcb.so.1
  NEEDED               libgbm.so.1
  NEEDED               libwayland-client.so.0
  NEEDED               libwayland-server.so.0
  NEEDED               libpthread.so.0
  NEEDED               libudev.so.1
  NEEDED               libdl.so.2
  NEEDED               libdrm.so.2
  NEEDED               libc.so.6

As you can see, it *also* links to the Wayland libs and libdrm, so I'm 
guessing this is to be expected. If you want to remove the dependency, we'd 
need to work with the Mesa people and create the MPA (Mesa Platform 
Abstraction).

I'm using Mesa 9.2.3.
-- 
Thiago Macieira - thiago.macieira (AT) intel.com
  Software Architect - Intel Open Source Technology Center