Core file unrecognized by gdb

I built the freedom-u-sdk on my ubuntu 16.04 dev machine. I cross compiled a program on the dev machine, copied the a.out to the freedom-unleashed board, ran the a.out there, got a core file, copied the core file back.

The cross-targeted gdb on the dev box doesn’t recognize the core file; gdb says (Elided):

This GDB was configured as “–host=x86_64-pc-linux-gnu --target=riscv64-unknown-linux-gnu”.

“core”: no core file handler recognizes format

yet running objdump says
freedom-u-sdk/toolchain/bin/riscv64-unknown-linux-gnu-objdump -x core

core: file format elf64-littleriscv
architecture: riscv:rv64, flags 0x00000000:

Is this inability to read core files expected?

freedom-u-sdk uses an old copy of riscv-gnu-toolchain that uses an old local port of gdb. I added core file support to FSF gdb over the summer and a few weeks ago I replaced the local gdb port in riscv-gnu-toolchain with the FSF gdb port. So if you git clone an up-to-date copy of riscv-gnu-toolchain this should work. But it isn’t expected to work with the toolchain in freedom-u-sdk.

freedom-u-sdk is what we use for demos. It isn’t meant to be a real linux system. If you want a real linux system, you should use debian, fedora, opensuse, openembedded/yocto, etc.

I got an up-to-date copy off riscv-gnu-toolchain, rebuilt the stack, and the tool chain seems to work fine at first look.

Thanks for the pointers!