Nothing critical, I compiled fully gcc 4.2.3 kernel + xaaes. The problem is, the resulting kernel is much slower at least in one case -- try to compile inet4.xdd and/or ethernat.xif with gcc4 and you'll see quite drastic slowdown in download speed.BTW, Anyone has managed to build Freemint kernel with Vincent's cygwin tools?
I remember I tried to compile the latest CVS version, hit has compiled, for sure ! The kernel ran... but because I hadn't compiled and setup the modules, etc... it didn't go very far.
There is currently no known problem with the C cross compiler 8-)
But GCC 4.x is a lot more severe than earlier versions, it produces more warnings, and sometimes errors. However, it is the same on other platforms. It is a good way to clean-up the sources.