If apitrace has its own old bundled copy of libbacktrace, better it should update it to the latest version, which is https://gcc.gnu.org/git/?p=gcc.git;a=tree;f=libbacktrace;h=7c4b8fb2fed26a741... Incomplete DWARF5 support was added to it in December 2019 and important bugfixes 9 days ago.
Thanks for your replies, I'll update the bundled libbacktrace and submit a PR upstream.
Sandro