Calling drop on an existing bcolz data directory results in an RuntimeError:
bcolz/carray_ext.pyx in bcolz.carray_ext.carray.flush (bcolz/carray_ext.c:31412)()
bcolz/carray_ext.pyx in bcolz.carray_ext.chunk.cinit (bcolz/carray_ext.c:4279)()
bcolz/carray_ext.pyx in bcolz.carray_ext.chunk.compress_data (bcolz/carray_ext.c:5222)()
RuntimeError: fatal error during Blosc compression: -1