[Bug target/25377] [4.2 Regression] weakref sibcalled with -fPIC

[pinskia at gcc dot gnu dot org]

------- Comment #3 from pinskia at gcc dot gnu dot org  2006-01-31 16:24 -------
Reduced testcase:
int f(void);
static typeof(f) g __attribute__((weakref("f")));
int h(void)
{
  return g();
}

-----
Actually is obviously why x86 goes wrong:
in ix86_function_ok_for_sibcall:
  /* If we are generating position-independent code, we cannot sibcall
     optimize any indirect call, or a direct call to a global function,
     as the PLT requires %ebx be live.  */
  if (!TARGET_64BIT && flag_pic && (!decl || TREE_PUBLIC (decl)))
    return false; 

TREE_PUBLIC Is the wrong check here. 

s390 fixed it a different correct way:
http://gcc.gnu.org/ml/gcc-patches/2005-12/msg00646.html

See the thread:
http://gcc.gnu.org/ml/gcc/2005-12/msg00718.html

Again checking TREE_PUBLIC is not the correct check really.
In fact reading tree.h, it seems so too as it is just commenting about the
name:
   nonzero means name is to be accessible from outside this module.

Which has nothing to do with the function being external.


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|middle-end                  |target
  GCC build triplet|i686-pc-linux-gnu           |
   GCC host triplet|i686-pc-linux-gnu           |
            Summary|[4.2 Regression] weak_ref   |[4.2 Regression] weakref
                   |sibcalled with -fPIC        |sibcalled with -fPIC


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25377