[Bug fortran/52469] [4.6/4.7/4.8 Regression] -fwhole-file bug: Wrong backend_decl for result of PPC function

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52469

Tobias Burnus <burnus at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |pault at gcc dot gnu.org

--- Comment #4 from Tobias Burnus <burnus at gcc dot gnu.org> 2012-03-05 20:31:58 UTC ---
WITH -fno-whole-file:

(gdb) b trans-expr.c:2249
...
Breakpoint 1, get_proc_ptr_comp (e=0x16d6420) at
/projects/tob/gcc-git/gcc/gcc/fortran/trans-expr.c:2249
2249      e2->expr_type = old_type;
(gdb) p debug_tree (comp_se.expr->typed.type)
 <function_type 0x2aaaacfb8b28
    type <real_type 0x2aaaacea1e70 real(kind=4) SF


WITH -fwhole-file:

(gdb) p debug_tree (comp_se.expr->typed.type)
 <pointer_type 0x2aaaacfb8bd0
    type <function_type 0x2aaaacfb8b28
        type <real_type 0x2aaaacea1e70 real(kind=4) SF


 * * *

Ignoring the difference, I tried:

--- a/gcc/fortran/trans-expr.c
+++ b/gcc/fortran/trans-expr.c
@@ -2250,2 +2250,4 @@ get_proc_ptr_comp (gfc_expr *e)
   gfc_free_expr (e2);
+  if (POINTER_TYPE_P (TREE_TYPE (comp_se.expr)))
+    return comp_se.expr; 
   return build_fold_addr_expr_loc (input_location, comp_se.expr);


However, that leads to a segfault at run time in the WRITE line - even though
the dump looks OK:

      real(kind=4) D.1871;
      static real(kind=4) C.1870 = 3.0e+0;
      D.1871 = newtype[1].my_f_ptr (&C.1870);
      _gfortran_transfer_real_write (&dt_parm.0, &D.1871, 4);

 * * *

I tried to find out what's the difference between -f(no-)whole file, but so far
without success. "gfc_get_ppc_type" is in both cases only called once and
returns a
 <pointer_type 0x2aaaacfb8bd0
    type <function_type 0x2aaaacfb8b28

Once, it is called directly:
  gfc_get_symbol_decl -> gfc_sym_type -> gfc_typenode_for_spec
  -> gfc_get_derived_type

And once indirectly:

  gfc_get_symbol_decl -> gfc_sym_type -> gfc_typenode_for_spec
  -> gfc_get_derived_type -> gfc_get_module_backend_decl ->
gfc_get_derived_type