March 1, 2021
After an hour of compiling RISC-V’s toolchain, I ran
remotely against my Rust kernel running in Qemu. This happened.
riscv64-unknown-elf-gdb \ -q \ -ex 'file target/riscv64gc-unknown-none-elf/debug/strail-rs' \ -ex 'target remote localhost:3333' \ -ex "b main" Reading symbols from target/riscv64gc-unknown-none-elf/debug/strail-rs... I'm sorry, Dave, I can't do that. Symbol format `elf64-littleriscv' unknown. Remote debugging using localhost:3333 make: *** [gdb] Abort trap: 6
What the hell. I immediately started to investigate what is going on, is it my build system? Is Rust compiling my binary in a wrong format (although it seems correct from the output)?
It seems that I did not configure RISC-V’s toolchain with
flag. The following solved the issue:
RISC-V toolchain compilation flags
./configure \ --prefix=$HOME/workspace/opt/riscv64 \ --with-arch=rv64imac \ --with-abi=lp64 \ --enable-multilib make -j8
One more hour wasted at compiling everything again. ❗ ️Update: This didn’t work. I ended up downloading RISC-V’s OSX pre-compiled
toolchain from their website. I need to find free time to figure out what flag I
❗ ️Update: This issue got addressed in GDB’s upstream, but for some reason RISC-V’s toolchain did not cherry-pick that commit. Either you cherry-pick that commit to your toolchain repository, or use GDB’s upstream.
See riscv-gnu-toolchain/issues/867 and thanks @jrtc27 for helping me out with the issue.
Fun fact: The error message
I'm sorry, Dave, I can't do that., comes from a
scene of A Space Odyssey (1968). It seems to have been committed in 28 March
1991, by K. Richard Pixley.