Det [1] filed a deletion request for mingw-w32-bin [2]:
"Actually the packages that are now in community seem to contain
everything to make 32 bit AND 64 bit windows binaries.
If you are thinking whether you want this package here, you probably
don't."
- uploader
[1] https://aur.archlinux.org/account/Det/
[2] https://aur.archlinux.org/pkgbase/mingw-w32-bin/