$ ./arm-linux-gcc --version
arm-linux-gcc (GCC) 3.4.3
Copyright (C) 2004 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
Checking my gcc binary it seems I'm running 3.4.3 (with the visibility patch), and without any problem. It's my understanding though that the kernel isn't even built with that cross compiler, but a prebuilt 2.95.3 toolchain so it's compatible with the closed source Sharp binaries.
If that's right, I can't imaging why 3.4.2 worked or made a difference. I think there's a good chance it was something else that made it successfull.