install the headers or librarys into the system.
someone who really cares could make them shlibs again and have them
installed into eg, /usr/lib/gcc. not convinced it is worth it.
MPC is a C library for the arithmetic of complex numbers with
arbitrarily high precision and correct rounding of the result.
It is built upon and follows the same principles as MPFR.
GCC >= 4.2 requires MPC.