John Marshall

I don't have an x86 machine handy to check on, but could this just be done with the built-in generic tests? e.g. ``` AC_CHECK_DECLS([__get_cpuid_max, __cpuid_count], [], [], [[#include ]]) ```

> Thoughts? If you fill in the actions-if-found and/or actions-if-not-found arguments, you can have your own simpler choice of macros to be defined instead of getting the default actions.

See also samtools/bcftools#1614 and #1448.