Currently, this is only relevant when using LevelDB, and a newer version
of libstdc++, which uses a different C++ ABI which clang does not yet support.
A symptom of the problem are unexpected linking failures, caused by undefined
symbols, while other symbols from the same library do not cause errors.
The solution is a workaround, that avoids using the offending symbols, at the
cost of reduced functionality. As this currently only affects the text of an
error message, the impact is minor.