[Bug ipa/70646] [4.9/5/6/7 Regression] Corrupt truncated function

["jpoimboe at redhat dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70646

--- Comment #24 from Josh Poimboeuf <jpoimboe at redhat dot com> ---
(In reply to Martin Jambor from comment #23)
> (In reply to Josh Poimboeuf from comment #20)
> > Thanks very much to everyone who has looked into this so far.  It would be
> > very helpful to get answers to the following questions, so we can understand
> > the impact to the kernel:
> > 
> > 1) Is there a reliable way to avoid the bug, either in code or with a gcc
> > flag?
> 
> If you mean in general, then unfortunately no, except for disabling
> inlining altogether and removing all always_inline's.  In addition to
> the main bug, I found out that I check --param ipa-max-agg-items only
> after incrementing it, so even setting that to zero does not help.
> I'll prepare a patch for that too.

Yes, I'm looking for a general way to either prevent or try to detect potential
other cases of the bug throughout the entire kernel.

Can it only occur with the use of __builtin_constant_p(exp) by an inline
function (where exp is a constant)?