lhs              = 0x123456789abcdef0
buggy (unsigned) = 0x0000000009abcdef   <-- truncated to 32 bits first
fixed (uintmax_t)= 0x0123456789abcdef
DDB session: 'x/s 0x123456789abcdef0 >> 4' evaluates to 0x9abcdef instead of 0x123456789abcdef