Most (if not all) of the K42 developers use gcc-3.3 to compile. Version 3.4 introduced a new C++ parser, which was more strict with the C++ standard. After a few changes, we now compile and boot using 3.4. However, there's a problem completing a regress-hw session - after testing, K42 tries to do a fast reboort, but dies with the following output:
KernelExit: muzzling interrupt controller.
CPUDead: pendingIntrs 0x0.
KernelExit: closing GDB.
Entry desc: 226c0 c000000002d336c0 [102ac,2a960]
KernelExit: copying reboot program.
Text: vaddr 0x0000000000010000 paddr 0x0000000000000009
size 0x00000000000024D0 offset 0xC000000002D31000
Data: vaddr 0x00000000000224D0 paddr 0x0000000000022978
size 0x00000000000004A8 offset 0xC000000002D334D0
BSS: vaddr 0x0000000000022978 paddr 0xC00000000C035000
size 0x0000000000000200
KernelExit: synchronizing caches.
Cache sync: 0xc000000000010000 - 0xc000000000022b78 80
KernelExit: launching ... iar:102ac sp:36b78 info:1ffc000
We haven't had any reports of compiling with gcc-4.0 yet. Leave a note if you have any luck with it!