It's hard to answer this completely without going into
some detail, so I offer you this for your reading pleasure
Just to avoid any misunderstanding, this is about this
patch for Qt 4.6.2 in current mingw-cross-env development:
qt-fix-configure-mac-windows.export
e2f6445c9c8c9fb046a3871f68950b7716663b0c
posted earlier today, 21 May
A good start, I applied that to a clean checkout.
[...snip long explanation - thanks for that]
In conclusion, I think
that this patch must be necessary for Qt 4.6.2 currently in
mingw-cross-env development. Can you confirm that it is both
necessary and sufficient?
Yes, it is necessary, the build succeeds, and the test program
runs. There is a slight difference in qconfig.h (defines
QT_ARCH_MACOSX instead of QT_ARCH_X86_64), but this looks
correct.