[Bug ipa/84833] [8 Regression] target_clones regression since r251047

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84833

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Martin Liška from comment #5)
> (In reply to Jakub Jelinek from comment #2)
> > Just a note, as can be seen e.g. on
> > static volatile int a;
> > static int my_foo1 (void) { return 1; }
> > static int my_foo2 (void) { return 2; }
> > typedef int (*F) (void);
> > static F resolve_foo (void) { if (a) return my_foo1; else return my_foo2; }
> > static int foo (void) __attribute__ ((ifunc ("resolve_foo")));
> > 
> > int
> > main ()
> > {
> >   if (foo () != 2)
> >     __builtin_abort ();
> > }
> > there is no reason why any of the target clones, resolver or the ifunc
> > function should be .globl, they can all be local to the TU, IFUNC work just
> > fine that way too.  So, if the function with target_clones attribute is not
> > TREE_PUBLIC, neither should be any of the multiple_targets.c created symbols.
> 
> If I see correctly, we do not make these global:
> 
> nm pr84833-2.o 
> 0000000000000000 b a
>                  U abort
> 000000000000000c i foo
> 0000000000000022 T main
> 0000000000000000 t my_foo1
> 0000000000000006 t my_foo2
> 000000000000000c t resolve_foo
> 
> Note that it was subject of PR81213.

nm is not really usable to determine if an IFUNC symbol is global or local, i
is printed regardless if it is global or local.
$ nm pr84833 | grep foo; readelf -Ws pr84833 | grep foo
0000000000400560 i foo
0000000000400540 t my_foo1
0000000000400550 t my_foo2
0000000000400560 t resolve_foo
    27: 0000000000400540     6 FUNC    LOCAL  DEFAULT   13 my_foo1
    28: 0000000000400550     6 FUNC    LOCAL  DEFAULT   13 my_foo2
    29: 0000000000400560    23 FUNC    LOCAL  DEFAULT   13 resolve_foo
    31: 0000000000400560    23 IFUNC   LOCAL  DEFAULT   13 foo
$ nm pr84833-2 | grep foo; readelf -Ws pr84833-2 | grep foo
0000000000400560 i foo
0000000000400540 t my_foo1
0000000000400550 t my_foo2
0000000000400560 t resolve_foo
    27: 0000000000400540     6 FUNC    LOCAL  DEFAULT   13 my_foo1
    28: 0000000000400550     6 FUNC    LOCAL  DEFAULT   13 my_foo2
    29: 0000000000400560    23 FUNC    LOCAL  DEFAULT   13 resolve_foo
    59: 0000000000400560    23 IFUNC   GLOBAL DEFAULT   13 foo
Where pr84833.c is the above #c2 testcase and pr84833-2.c is that without
static keyword on foo.

These testcases are compiled fine, what I was trying to make sure is that if
the target_clones function is static, it is not exported outside of the TU.