On Wed, 14 Mar 2018, Jason Vas Dias wrote: > gcc-4.8.5-16 (20150623) + binutils as 2.25.1-32.base.el7_4.2 here > that is causing references to __x86_indirect_thunk_rax to be > inserted in the above switch with more than 4 clauses whenever > 'gtod' is referenced . The patch I sent avoids the problem, but > why does the problem arise with the new GCC version and > not the old one ? Is this the gcc with the reptoline fixes for Spectre ? I understand that firefox reduced the precision of several clocks https://blog.mozilla.org/security/2018/01/03/mitigations-landing-new-class-timing-attack/ to mitigate Meltdown and Spectre. Could gcc and/or the kernel be doing the same thing ? -- Andrew C. Aitchison Cambridge, UK [log in to unmask]