Checking for an RDRAND or RDSEED failure in inline assembly

Question

I am trying to test for an error in RDRAND and RDSEED using MSVC-style inline assembly. If I remember correctly a flag for failure is stored in a register, but I cannot remember which one. I have seen an example on Intel's website

    asm volatile ("rdrand %0; setc %1"
    : "=r" (*rand), "=qm" (ok));

where "=qm" and "ok" indicate a failure if not equal to 1, but I am relatively unfamiliar with GCC-style inline assembly, so I do not know what "=qm" means, and I have not been able to figure it out. How can I determine success or failure in MSVC-style inline assembly?

Thanks in advance.