load mpfr-dev, libmpc-dev extensions

gmp-5.0.2
---------
CFLAGS='-march=i486 -mtune=i686 -Os -pipe' CXXFLAGS='-march=i486 -mtune=i686 -Os -pipe' ABI=32 ./configure --prefix=/usr/local --enable-cxx --enable-mpbsd --host=i486-pc-linux-gnu

make real    2m 1.11s
sudo make install

using ABI="32"
      CC="gcc -std=gnu99"
      CFLAGS="-march=i486 -mtune=i686 -Os -pipe"
      CPPFLAGS=""
      CXX="g++"
      CXXFLAGS="-march=i486 -mtune=i686 -Os -pipe"
      MPN_PATH=" x86/i486 x86 generic"