Nope. Intel's MPX is an opt-in thing to assist with pointer bounds checking.

caf · on May 4, 2016

I was thinking of MPK, not MPX.

You'd set the library's code and data pages to protection key 1, along with the page containing a library access trampoline, leaving the rest of the address space with protection key 0. You'd call into the library through the trampoline, which would revoke access to protection key 0, call into the library, then restore access to key 0.