[Bug fortran/78618] ICE in gfc_check_rank, at fortran/check.c:3670

[janus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78618

--- Comment #19 from janus at gcc dot gnu.org ---
(In reply to Steve Kargl from comment #18)
> On Sun, Dec 04, 2016 at 04:24:21PM +0000, janus at gcc dot gnu.org wrote:
> > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78618
> > 
> > Maybe one can instead try to nullify the memory in gfc_free charlen, so that we
> > at least know that cl->lengh is not a valid pointer? (Something similar is also
> > done in gfc_free_expr / free_expr0 in expr.c.)
> > 
> > Index: symbol.c
> > ===================================================================
> > --- symbol.c    (revision 243224)
> > +++ symbol.c    (working copy)
> > @@ -3838,6 +3838,7 @@ gfc_free_charlen (gfc_charlen *cl, gfc_charlen *en
> > 
> >        cl2 = cl->next;
> >        gfc_free_expr (cl->length);
> > +      memset (cl, '\0', sizeof (gfc_charlen));
> >        free (cl);
> >      }
> >  }
> > 
> 
> Doesn't that leak memory?  The 'free(cl)' in the line
> after memset() should be a NOP, so whatever cl pointed
> to before the memset() is leaked.

I guess memset does not nullify the pointer 'cl' itself, but the memory it
points to, right? (As mentioned, we do the same thing in gfc_free_expr.)


> Hmmm, doesn't seem to help.

Too bad :(