mingw sysroot paths (and generalizing them)

Looking at Information for RPM mingw64-zlib-1.2.13-2.fc38.noarch.rpm <https://koji.fedoraproject.org/koji/rpminfo?rpmID=33118048> sysroot paths look like this: /usr/x86_64-w64-mingw32/sys-root/mingw/bin/zlib1.dll /usr/x86_64-w64-mingw32/sys-root/mingw/include/zconf.h /usr/x86_64-w64-mingw32/sys-root/mingw/include/zlib.h /usr/x86_64-w64-mingw32/sys-root/mingw/lib/libz.dll.a /usr/x86_64-w64-mingw32/sys-root/mingw/lib/pkgconfig/zlib.pc Is the /mingw/ part of the sysroot path, or is it within the sysroot? Would I use --sysroot=/usr/x86_64-w64-mingw32/sys-root or --sysroot=/usr/x86_64-w64-mingw32/sys-root/mingw to build against the sysroot? I assumed the latter, but now I wonder if /mingw in the sysroot is the analogue of /usr in GNU/Linux sysroots. Eventually, we want to produce some GNU/Linux sysroots. I picked /usr/%{_arch}-redhat-linux/sys-root/fc%{fedora} or (depending on the operating system) /usr/%{_arch}-redhat-linux/sys-root/el%{rhel} or (as the fallback) /usr/%{_arch}-redhat-linux/sys-root/root and we have /usr inside the sysroot, e.g. <stdio.h> is /usr/x86_64-redhat-linux/sys-root/fc35/usr/include/stdio.h in a Fedora 35 sysroot on x86-64 (although the Fedora 35 update with this never actually went out). We essentially use the /mingw/ part as an OS ABI version indicator, to make the different versions co-installable. I want to pick this up again and would like to solicit comments if that OS ABI variant thing is the right approach, or if we should drop it. Sysroot packages are by nature relocatable, and do not have to be installed in /, so it's perhaps not a great loss if their version variants are not co-installable. We need something like this before we can drop i686 on ELN; it's only way to enable -m32 in GCC in a sustainable fashion. But we don't need OS ABI variants for that. Thanks, Florian