[Bug fortran/57079] New: [Fortran-dev] version/type/attribute fields not set with CLASS components

[Bug fortran/57079] New: [Fortran-dev] version/type/attribute fields not set with CLASS components

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57079

             Bug #: 57079
           Summary: [Fortran-dev] version/type/attribute fields not set
                    with CLASS components
    Classification: Unclassified
           Product: gcc
           Version: fortran-dev
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: burnus@gcc.gnu.org
                CC: pault@gcc.gnu.org
            Blocks: 56818


The following test case shows that the version etc. field is not properly set
for:

subroutine foo()
  type t2
  end type t2
  type t
    integer, allocatable :: x(:)
    class(t2), allocatable :: y(:)
    integer :: z = 55
  end type t
  type(t), allocatable :: x!(:)
   allocate(x)
end

I wrote that it is a CLASS problem, but it might also affect other allocatable
components if there is a default initializer.


The problem is that the following code is generated, i.e. the initialization is
overridden. The additional issue is that there is a missed optimization
(setting the same value multiple times) - which should be avoided if possible.
There might be also other cases, where the fields aren't properly set.


        x = (struct t *) __builtin_malloc (128);
      ...
      x->x.base_addr = 0B;
      x->x.version = 1;
      ...
      x->y._data.base_addr = 0B;
      x->y._data.version = 1;
      ...
      {
        struct t t.0;

        if (x != 0B) goto L.1;
        x = (struct t *) __builtin_calloc (1, 128);
        L.1:;
        t.0.x.base_addr = 0B;
        t.0.y._data.base_addr = 0B;
        t.0.y._vptr = (struct __vtype_foo_T2 * {ref-all}) &__vtab_foo_T2;
        t.0.z = 55;
        *x = t.0;

[Bug fortran/57079] [Fortran-dev] version/type/attribute fields not set with CLASS components

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57079

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

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

--- Comment #1 from Tobias Burnus <burnus at gcc dot gnu.org> 2013-04-26 07:46:41 UTC ---
(In reply to comment #0)
> There might be also other cases, where the fields aren't properly set.

In particular, I think, one should check:
- ALLOCATE with SOURCE=
- CLASS(*) - also as DT component
- Pointer assignment "=>" - especially with CLASS(dt)/CLASS(*)

On the other hand, some values are currently reseted but should have the same
value, e.g. "type" is set at declaration time (or for components: when the
encompassing DT is allocated). In that case, the only case where "type" has to
be set is for CLASS(*) [type = other vs. type = <intrinsic type>] and in case
of "elem_len" for CLASS(dt)/CLASS(*).

[Bug fortran/57079] [Fortran-dev] version/type/attribute fields not set with CLASS components

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57079

Dominique d'Humieres <dominiq at lps dot ens.fr> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |WAITING
   Last reconfirmed|                            |2014-03-22
     Ever confirmed|0                           |1

--- Comment #2 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
What is the problem with this pr? The difference between the dump with trunk
(r208766) and the dev branch (r208422) is

--- pr57079.f90.003t.original    2014-03-22 20:11:30.000000000 +0100
+++ pr57079.f90_dev.003t.original    2014-03-22 20:10:59.000000000 +0100
@@ -14,28 +14,38 @@ foo ()
   try
     {
       x = 0B;
-      if (x != 0B)
+      if ((logical(kind=4)) __builtin_expect ((integer(kind=8)) (x != 0B), 0))
         {
           _gfortran_runtime_error_at (&"At line 10 of file pr57079.f90"[1]{lb:
1 sz: 1}, &"Attempting to allocate already allocated variable \'%s\'"[1]{lb: 1
sz: 1}, &"x"[1]{lb: 1 sz: 1});
         }
       else
         {
-          x = (struct t *) __builtin_malloc (112);
-          if (x == 0B)
+          x = (struct t *) __builtin_malloc (128);
+          if ((logical(kind=4)) __builtin_expect ((integer(kind=8)) (x == 0B),
0))
             {
               _gfortran_os_error (&"Allocation would exceed memory
limit"[1]{lb: 1 sz: 1});
             }
         }
-      x->x.data = 0B;
-      x->y._data.data = 0B;
+      x->x.base_addr = 0B;
+      x->x.elem_len = 4;
+      x->x.version = 1;
+      x->x.rank = 1;
+      x->x.type = 1025;
+      x->x.attribute = 2;
+      x->y._data.base_addr = 0B;
+      x->y._data.elem_len = 0;
+      x->y._data.version = 1;
+      x->y._data.rank = 1;
+      x->y._data.type = -1;
+      x->y._data.attribute = 1;
       {
         struct t t.0;

         if (x != 0B) goto L.1;
-        x = (struct t *) __builtin_calloc (1, 112);
+        x = (struct t *) __builtin_calloc (1, 128);
         L.1:;
-        t.0.x.data = 0B;
-        t.0.y._data.data = 0B;
+        t.0.x.base_addr = 0B;
+        t.0.y._data.base_addr = 0B;
         t.0.y._vptr = (struct __vtype_foo_T2 * {ref-all}) &__vtab_foo_T2;
         t.0.z = 55;
         *x = t.0;
@@ -45,20 +55,20 @@ foo ()
     {
       if (x != 0B)
         {
-          if (x->x.data != 0B)
+          if (x->x.base_addr != 0B)
             {
-              __builtin_free ((void *) x->x.data);
+              __builtin_free ((void *) x->x.base_addr);
             }
-          x->x.data = 0B;
-          if ((struct t2[0:] * restrict) x->y._data.data != 0B &&
x->y._vptr->_final != 0B)
+          x->x.base_addr = 0B;
+          if ((struct t2[0:] * restrict) x->y._data.base_addr != 0B &&
x->y._vptr->_final != 0B)
             {
               x->y._vptr->_final (&x->y._data, (integer(kind=8))
x->y._vptr->_size, 1);
             }
-          if (x->y._data.data != 0B)
+          if (x->y._data.base_addr != 0B)
             {
-              __builtin_free ((void *) x->y._data.data);
+              __builtin_free ((void *) x->y._data.base_addr);
             }
-          x->y._data.data = 0B;
+          x->y._data.base_addr = 0B;
           __builtin_free ((void *) x);
         }
     }

[Bug fortran/57079] [Fortran-dev] version/type/attribute fields not set with CLASS components

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57079

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Something changed in GCC 8 and we get:
  <bb 4> :
  x_22 = __builtin_malloc (144);
  if (x_22 == 0B)
    goto <bb 5>; [INV]
  else
    goto <bb 6>; [INV]

  <bb 5> :
  _gfortran_os_error (&"Allocation would exceed memory limit"[1]{lb: 1 sz: 1});
...
And no more __builtin_calloc either.