Zen 4 reporting in. I'm unable to reproduce it (7840U).
$ ./a.out | rg '\b\-?\d\b' | sort -n | uniq -c
15281 -2
15192 -1
15273 0
15243 1
15269 2
I used the GCC intrinsic ( _rdrand16_step ), #include <immintrin.h>
short rdrand16() { // gcc -mrdrnd
short ret;
while (1 != _rdrand16_step(&ret)) { }
return ret;
}