Sorry Thad, I want to correct something I said: I recommended that you try the arm-linux-gnueabihf toolchain, but that should have been the arm-linux-gnueabi toolchain.

Aside from that, I went and double checked, and this toolchain works just fine -- one thing to note though, is that you don't have to specify the -DCROSS_COMPILER_PREFIX=foo option, and you should be able to just use -DAARCH32=1 and our build system should automatically select the right toolchain to invoke for you (see: https://github.com/seL4/seL4/blob/master/gcc.cmake#L24​)

Feel free to ask more questions about the new build system since we expect adaptation to take some time.