[Interest] Qt 5.0.2 speed and widgets

[Philippe]

Compared to Qt 4.8.x, I experiment a very sensible reduction of speed
in 5.0.2 when widgets are created or complex windows activated.
In Release mode this is "sort of acceptable",... maybe half speed.
But in debug mode, this is dramatically slower, up to 6x slower than in
4.8.3.

This is not a painting issue as the speed inside a window has been
measured to be sensibly the same to 4.8.x (using ANGLE).

Anyone else sees the same? Any known reason for this?

Setup: Windows 7, Visual 2010, Qt 32 bit, *very* fast computer.

Philippe