Using latest ecl from source when I try to asdf load any package that
depends on cffi I get the error like "cannot find external symbol
call-cfun in SI package".
In your case I believe the error is caused by libffi not being available: without libffi ECL can only code the FFI using C. Can you verify whether *features* contains :DFFI? Could it be that the library you try to load was built with a previous version of ECL?