dang, i'm having to use the freedom-sdk to build riscv64-unknown-linux-gcc-7.2.0 as i am trying to get spike running a linux kernel and basic OS. hopefully you won't have to do that, daniel, and the riscv-tools are up-to-date enough to generated riscv64-unknown-elf-gcc-7.2.0 usefully (note the difference in the compiler names...)