Test platform is 32 bit Linux.
Basically, I know gcc can be used to generate both Intel and At&T style assembly code, but it seems that you can not<
Heres a way to do it without objconv
objconv
ndisasm -u <(objdump -j .text -d main.o | cut -d: -f2 | cut -d$'\t' -f 2 | perl -ne 'next if /file/; s/\s+//g; print' | xxd -r -p)