Without the change build fails on upstream gcc-10 as:
ld: ccD2iWhk.o:(.bss+0x8): multiple definition of `domain';
ccgA4lYl.o:(.bss+0x8): first defined here
ld: ccD2iWhk.o:(.bss+0x0): multiple definition of `long_domain';
ccgA4lYl.o:(.bss+0x0): first defined here