[Bug lto/60061] Different dump-ipa-cp-details without/with -flto for gfortran.dg/pr53787.f90

["rguenth at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60061

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2014-02-05
                 CC|                            |jamborm at gcc dot gnu.org
     Ever confirmed|0                           |1

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
The dumps seem to be different for the Jump functions already.  It seems that
passing -flto makes the machinery behave differently for some reason
(note this is compile-stage only so make sure to also pass -ffat-lto-objects).

Martin?  Honza?

Maybe this is because of

ipa_compute_jump_functions (struct cgraph_node *node,
                            struct param_analysis_info *parms_ainfo)
{
  struct cgraph_edge *cs;

  for (cs = node->callees; cs; cs = cs->next_callee)
    {
      struct cgraph_node *callee = cgraph_function_or_thunk_node (cs->callee,
                                                                  NULL);
      /* We do not need to bother analyzing calls to unknown
         functions unless they may become known during lto/whopr.  */
      if (!callee->definition && !flag_lto)
        continue;

?  Or other flag_lto tests?  Or maybe this is just because -fwhole-program
is interpreted differently when used with/without -flto?  Indeed the
actual transforms of -flto -fwhole-program match those of -fno-lto
-fno-whole-program.