http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53112
--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> 2012-04-30 11:51:06 UTC --- (In reply to comment #4) > Sorry buddy, I have removed past code and setup the fresh code. > > This time have build 64 bit gmp and mpfr with ABI=64 @ --prefix path > /usr/local/ and tried to build gcc in 64 bit. but it gave this error > ELFCLASS64 > for libmpfr.so and libgmp.so Don't do that. GCC 4.4 always builds a 32-bit binary on Solaris, so it needs 32-bit GMP and MPFR libs. But if you follow the instructions at http://gcc.gnu.org/wiki/InstallingGCC then you don't need to install GMP and MPFR anyway, GCC will automatically buil them correctly for you.