gcc-4.7 fails to build rtems-4.11/gcc-4.6

[Ralf Corsepius]

Hi,

When rebuilding the rtems-4.11 toolchains for Fedora 17/rawhide,
I tripped over a pretty nasty bug in gcc-4.6:

http://gcc.gnu.org/ml/gcc/2012-01/msg00292.html
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51969

This affects all gcc-4.6-based RTEMS-4.11 toolchains (i.e. all targets 
but the lm32).

On the positive side
- a work-around is known (c.f. GCC BZ 51969)
- This bug only shows when using a gcc-4.7 based native GCC
   to build gcc-4.6.x-based toolchains.

I am going to adopt the work-around to the rtems-gcc-4.6.2 patches.

Ralf