libstdc++ is a C++ standard library plus extensions like SGI's STL (standard template library). It was compiled and is intended for use with g++ from gcc 2.8.1 (a separate freeware package).
libstdc++-2.8.1: description + notes
Note that unlike in C, you may not mix modules compiled the SGI C compiler with the GNU libstdc++ library since g++ and the SGI C++ compiler use completely different mangling schemes.
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