Building QEMU on Gentoo

QEMU won't compile properly with GCC version 4. On Gentoo, you can revert to another installed GCC version using the gcc-config command:

$ gcc-config -l
 [1] x86_64-pc-linux-gnu-3.4.6
 [2] x86_64-pc-linux-gnu-3.4.6-hardened
 [3] x86_64-pc-linux-gnu-3.4.6-hardenednopie
 [4] x86_64-pc-linux-gnu-3.4.6-hardenednopiessp
 [5] x86_64-pc-linux-gnu-3.4.6-hardenednossp
 [6] x86_64-pc-linux-gnu-4.1.2 *

$ gcc-config 1
$ source /etc/profile
$ emerge -av app-emulation/qemu