+ // Always inline in order for this to be usable from a __ifunc__.
+ // In shared library mode, a __ifunc__ runs at relocation time, while the
+ // PLT hasn't been fully populated yet; thus, ifuncs cannot use symbols
+ // with potentially external linkage. (This issue is less likely in opt
+ // mode since inlining happens more likely, and it doesn't happen for
+ // statically linked binaries which don't depend on the PLT)
+ FOLLY_ALWAYS_INLINE CpuId() {