AOSP Nougat turns on lzma support on libunwind, but it seems that's going to take some time to implement it. On Debian, three lzma related libraries available: liblzma-dev, lzma-dev and 7z.so from p7zip-full. Android uses a fork from the last one, which comes with no header in Debian default install. Official libunwind uses liblzma-dev, and that has been rewritten to prefer p7zip in Android.
AOSP Nougat turns on lzma support on libunwind, but it seems that's going to take some time to implement it. On Debian, three lzma related libraries available: liblzma-dev, lzma-dev and 7z.so from p7zip-full. Android uses a fork from the last one, which comes with no header in Debian default install. Official libunwind uses liblzma-dev, and that has been rewritten to prefer p7zip in Android.