cross compiling with the C backend

Hello, Kevin.

Well, I already use custom includes with these options: "-nostdlib
-nostdinc -Ipsptoolchain/psp/include
-Ipsptoolchain/lib/gcc/psp/4.1.0/include". But that seems not enough.
GCC has some target-specific behaviour compiled in?

Well, in general - yes. However, I'm not sure up to which margin.

So I don't really have any other choice than hacking llvm-gcc?