rebuild expat with: CFLAGS="-march=core2 -O3 -fomit-frame-pointer -fexpensive-optimizations" ./configure --prefix=/mingw64/x86_64-w64-mingw32 --disable-shared --enable-static
remove unused file
update curl to curl-7.29.0, build with: CFLAGS="-march=core2 -O3 -fomit-frame-pointer -fexpensive-optimizations" LIBS=-lz ./configure --prefix=/mingw64/x86_64-w64-mingw32 --disable-shared --enable-static --disable-ldap --with-ssl=/mingw64/x86_64-w64-mingw32 --with-zlib=/mingw64/x86_64-w64-mingw32
remove unused files