winegcc from wine64-tools produces a 32-bit object if "-m32" is specified, as expected. wine64-tools needs to be installed manually to avoid the 64-bit libwine-dev.
gcc-multilib cannot have Multi-Arch set to "foreign" or "allowed". That would allow gcc-multilib:any. It would mean that a powerpc system could use the i386 gcc-multilib to produce ppc64 binaries. "-m32" is really necessary in amd64 to compile 32-bit programs. This could be mentioned in a README, but this is like gcc-multilib: winegcc works like gcc. Regarding perl, you may want to see https://bugs.debian.org/824696 . perl is needed for winemaker.
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