AMD's random number generator can't generate a 0?

A developer discovered that AMD processors (possibly Zen2 architecture) fail to generate the value 0 when using the rdrand and rdseed random number generator instructions, while Intel processors generate 0 normally. The issue can be worked around by generating larger bit-width random numbers (32 or 64-bit) and extracting the desired lower bits, rather than requesting exact-sized random numbers directly.