libstdc++-8-pic-mips64-cross 8-20180414-1ubuntu2cross1 (amd64 binary) in ubuntu cosmic

 This is used to develop subsets of the libstdc++ shared libraries for
 use on custom installation floppies and in embedded systems.
 .
 Unless you are making one of those, you will not need this package.
 .
 This package contains files for mips64 architecture, for use in cross-compile
 environment.