I remember old emails where, with your help, I had managed to compile
without thirdparty. I can't find that thread anymore; does anyone
remember what it was? The fact is that I forgot how to do such a
build.
you can look into "bld" directory - BSDs build work exactly without thirdparty (shortened):
./configure --with-single-user \
--disable-static-build --without-thirdparty --without-libdpx
May be we should add this to manual .
Another question: should I still use the two "exports" in this build as well?
No, because build will attempt to link to already-build libav* libraries.