[Bug c/63307] [4.9/5 Regression] Cilk+ breaks -fcompare-debug bootstrap

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63307

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Igor Zamyatin from comment #3)
> (In reply to Jakub Jelinek from comment #2)
> 
> > 
> > > +  vec_arglist.release();
> > 
> > Formatting.  You could use auto_vec, perhaps with some stack allocated
> > initial buffer if you think say 16 vector elements would be typically enough.
> 
> Is it ok to have auto_vec declaration outside the routine?

Why do you need to declare it outside of the routine?  That seems undesirable
to me.

> > Also, what about all the remaining 3 callbacks that create or may create
> > decls and have the same problem?  for_local_cb, wrapper_local_cb and
> > declare_one_free_variable.
> 
> These are callbacks that seem to be safe in the sense of random ordering - 
> perform some 1 to 1 mapping

I don't think so.  They copy declarations, i.e. create new declarations, and
the different ordering of their DECL_UID values may result in code generation
differences (e.g. various other spots in the compiler sort based on DECL_UIDs,
if you create them in pretty random order, you'll surely trigger some
-fcompare-debug (perhaps not with current limited testsuite coverage, but with
other tests).