When building libgcrypt 1.9.1 on NetBSD 9.99.79/amd64, I see:
`
--- keccak.lo ---
keccak.c: In function 'keccak_init':
keccak.c:907:23: error: 'HWF_INTEL_FAST_SHLD' undeclared (first use in this function)
907 | else if (features & HWF_INTEL_FAST_SHLD)
| ^~~~~~~~~~~~~~~~~~~
keccak.c:907:23: note: each undeclared identifier is reported only once for each function it appears in
`This did not happen in 1.9.0.