tce-load -i

cd libpng-1.6.2

gzip -cd ../libpng-1.6.2-apng.patch.gz | patch -p1

CC="gcc -flto -fuse-linker-plugin -march=i486 -mtune=i686 -Os -pipe" CXX="g++ -flto -fuse-linker-plugin -march=i486 -mtune=i686 -Os -pipe -fno-exceptions -fno-rtti" ./configure --prefix=/usr/local

CFLAGS="-march=i486 -mtune=i686 -Os -pipe" CXXFLAGS=" -march=i486 -mtune=i686 -Os -pipe -fno-exceptions -fno-rtti" ./configure --prefix=/usr/local

no difference in size

make
sudo make install