ELF files generated for X86_64 targets may contain 64-bit PC-relative relocations. For instance, an exception handler table entry contains the start of exception-throwing frame relative to the start of exception handler. As these two labels belong to different sections, their difference and so the relocation is 64-bit.
An attempt to parse such file, i.e. in DWARFContext::create, results in "failed to compute relocation" error.
The proposed simple and straightforward fix adds support for such relocations to RelocationResolver.cpp.