export CFLAGS="-march=i486 -mtune=i686 -Os -pipe"
export CXXFLAGS="-march=i486 -mtune=i686 -Os -pipe"
export PKG_CONFIG_PATH=/usr/lib/pkgconfig:/usr/local/lib/pkgconfig

libsigc++-2.2.4.2
-----------------
./configure --prefix=/usr/local --disable-documentation

make
sudo make install-strip