For openSUSE Tumbleweed PowerPC run the following as root:
zypper addrepo https://download.opensuse.org/repositories/windows:mingw:win32/openSUSE_Tumbleweed_PowerPC/windows:mingw:win32.repo
zypper refresh
zypper install mingw32-gcc
For openSUSE Tumbleweed ARM run the following as root:
zypper addrepo https://download.opensuse.org/repositories/windows:mingw:win32/openSUSE_Tumbleweed_ARM/windows:mingw:win32.repo
zypper refresh
zypper install mingw32-gcc
For openSUSE Tumbleweed run the following as root:
zypper addrepo https://download.opensuse.org/repositories/windows:mingw:win32/openSUSE_Tumbleweed/windows:mingw:win32.repo
zypper refresh
zypper install mingw32-gcc