On 18/01/16 17:10, Eric Botcazou wrote:
Similarly to ARM, I note that Ada is affected. Indeed, with a gcc 4.9 host
compiler, I saw a bootstrap miscompare iff including Ada; however, I was
able to bootstrap Ada successfully, if I first built a GCC including this
patch with --disable-bootstrap, and then used that as host compiler. The
best explanation I can see for this is mismatched host vs built libraries
and compiler being used together, something like Jakub's suggestion
http://gcc.gnu.org/ml/gcc-patches/2015-11/msg00338.html. I don't feel I have
the expertise for this, and am CCing the Ada maintainers in the hope they
can help.
That's a bit weird though because this should have also occurred for ARM when
the ABI was broken the same way if the Ada bootstrap is not entirely correct.
Now, as far I know, this didn't occur for ARM during bootstrap but only during
testing with make -k check. Or else could this be a parallel compilation bug?
Could you post the list of files that differ? How do they differ exactly?
Hmmm. Well, I definitely had this failing to bootstrap once. I repeated that, to
try to identify exactly what the differences were....and it succeeded even with
my pre-AAPCS64-update host compiler. So, this is probably a false alarm; I'm
bootstrapping again, after a rebase, to make sure...
--Alan
