This option enables functions containing calls to intrinsics that require a
specific CPU feature to have their target architecture automatically promoted
to allow the required feature.
All code within the function will be compiled with that target architecture,
and the resulting code for such functions will not execute correctly on
processors that do not support the required feature.
You are responsible for guarding the execution path at run time so that such
functions are not dynamically reachable when the program is run on processors
that do not support the required feature.
We recommend that you use
__attribute__((target(<required target>))) to mark functions that are
intended to be executed on specific target architectures instead of using this
option. This attribute will provide significantly better compile time error