[Patch, fortran] PR49213 - [OOP] gfortran rejects structure constructor expression

[Patch, fortran] PR49213 - [OOP] gfortran rejects structure constructor expression

[Paul Richard Thomas]

[-- Attachment #1: Type: text/plain, Size: 1456 bytes --]

Hi All,

I was looking through Neil Carlson's collection of gfortran bugs and
was shocked to find this rather fundamental PR. At 12 years old, it is
certainly a "golden oldie"!

The patch is rather straightforward and seems to do the job of
admitting derived, intrinsic and character expressions to allocatable
class components in structure constructors.

I have included the adjustment to 'gfc_is_ptr_fcn' and eliminating the
extra blank line, introduced by my last patch. I played safe and went
exclusively for class functions with attr.class_pointer set on the
grounds that these have had all the accoutrements checked and built
(ie. class_ok). I am still not sure if this is necessary or not.

OK for trunk?

Paul

Fortran: Enable class expressions in structure constructors [PR49213]

2023-06-24  Paul Thomas  <pault@gcc.gnu.org>

gcc/fortran
PR fortran/49213
* expr.cc (gfc_is_ptr_fcn): Guard pointer attribute to exclude
class expressions.
* resolve.cc (resolve_assoc_var): Call gfc_is_ptr_fcn to allow
associate names with pointer function targets to be used in
variable definition context.
* trans-decl.cc (get_symbol_decl): Remove extraneous line.
* trans-expr.cc (alloc_scalar_allocatable_subcomponent): Obtain
size of intrinsic and character expressions.
(gfc_trans_subcomponent_assign): Expand assignment to class
components to include intrinsic and character expressions.

gcc/testsuite/
PR fortran/49213
* gfortran.dg/pr49213.f90 : New test

[-- Attachment #2: pr49213.diff --]
[-- Type: text/x-patch, Size: 5161 bytes --]

diff --git a/gcc/fortran/expr.cc b/gcc/fortran/expr.cc
index c960dfeabd9..92061d69781 100644
--- a/gcc/fortran/expr.cc
+++ b/gcc/fortran/expr.cc
@@ -816,7 +816,7 @@ bool
 gfc_is_ptr_fcn (gfc_expr *e)
 {
   return e != NULL && e->expr_type == EXPR_FUNCTION
-	      && (gfc_expr_attr (e).pointer
+	      && ((e->ts.type != BT_CLASS && gfc_expr_attr (e).pointer)
 		  || (e->ts.type == BT_CLASS
 		      && CLASS_DATA (e)->attr.class_pointer));
 }
diff --git a/gcc/fortran/resolve.cc b/gcc/fortran/resolve.cc
index 82e6ac53aa1..217d69d4e0b 100644
--- a/gcc/fortran/resolve.cc
+++ b/gcc/fortran/resolve.cc
@@ -1350,6 +1350,9 @@ resolve_structure_cons (gfc_expr *expr, int init)
 	  && CLASS_DATA (comp)->as)
  	rank = CLASS_DATA (comp)->as->rank;
 
+      if (comp->ts.type == BT_CLASS && cons->expr->ts.type == BT_DERIVED)
+	  gfc_find_derived_vtab (cons->expr->ts.u.derived);
+
       if (cons->expr->expr_type != EXPR_NULL && rank != cons->expr->rank
 	  && (comp->attr.allocatable || cons->expr->rank))
 	{
@@ -1381,7 +1384,7 @@ resolve_structure_cons (gfc_expr *expr, int init)
 			 gfc_basic_typename (comp->ts.type));
 	      t = false;
 	    }
-	  else
+	  else if (!UNLIMITED_POLY (comp))
 	    {
 	      bool t2 = gfc_convert_type (cons->expr, &comp->ts, 1);
 	      if (t)
diff --git a/gcc/fortran/trans-decl.cc b/gcc/fortran/trans-decl.cc
index 18589e17843..b0fd25e92a3 100644
--- a/gcc/fortran/trans-decl.cc
+++ b/gcc/fortran/trans-decl.cc
@@ -1915,7 +1915,6 @@ gfc_get_symbol_decl (gfc_symbol * sym)
 	gcc_assert (!sym->value || sym->value->expr_type == EXPR_NULL);
     }
 
-
   gfc_finish_var_decl (decl, sym);
 
   if (sym->ts.type == BT_CHARACTER)
diff --git a/gcc/fortran/trans-expr.cc b/gcc/fortran/trans-expr.cc
index 3c209bcde97..5a1ff0c1d21 100644
--- a/gcc/fortran/trans-expr.cc
+++ b/gcc/fortran/trans-expr.cc
@@ -8781,6 +8781,7 @@ alloc_scalar_allocatable_subcomponent (stmtblock_t *block, tree comp,
   tree size;
   tree size_in_bytes;
   tree lhs_cl_size = NULL_TREE;
+  gfc_se se;
 
   if (!comp)
     return;
@@ -8815,16 +8816,26 @@ alloc_scalar_allocatable_subcomponent (stmtblock_t *block, tree comp,
     }
   else if (cm->ts.type == BT_CLASS)
     {
-      gcc_assert (expr2->ts.type == BT_CLASS || expr2->ts.type == BT_DERIVED);
-      if (expr2->ts.type == BT_DERIVED)
+      if (expr2->ts.type != BT_CLASS)
 	{
-	  tmp = gfc_get_symbol_decl (expr2->ts.u.derived);
-	  size = TYPE_SIZE_UNIT (tmp);
+	  if (expr2->ts.type == BT_CHARACTER)
+	    {
+	      gfc_init_se (&se, NULL);
+	      gfc_conv_expr (&se, expr2);
+	      size = fold_convert (size_type_node, se.string_length);
+	    }
+	  else
+	    {
+	      if (expr2->ts.type == BT_DERIVED)
+		tmp = gfc_get_symbol_decl (expr2->ts.u.derived);
+	      else
+		tmp = gfc_typenode_for_spec (&expr2->ts);
+	      size = TYPE_SIZE_UNIT (tmp);
+	    }
 	}
       else
 	{
 	  gfc_expr *e2vtab;
-	  gfc_se se;
 	  e2vtab = gfc_find_and_cut_at_last_class_ref (expr2);
 	  gfc_add_vptr_component (e2vtab);
 	  gfc_add_size_component (e2vtab);
@@ -8975,6 +8986,7 @@ gfc_trans_subcomponent_assign (tree dest, gfc_component * cm,
     {
       gfc_init_se (&se, NULL);
       gfc_conv_expr (&se, expr);
+      tree size;
 
       /* Take care about non-array allocatable components here.  The alloc_*
 	 routine below is motivated by the alloc_scalar_allocatable_for_
@@ -8990,7 +9002,7 @@ gfc_trans_subcomponent_assign (tree dest, gfc_component * cm,
 	  && expr->symtree->n.sym->attr.dummy)
 	se.expr = build_fold_indirect_ref_loc (input_location, se.expr);
 
-      if (cm->ts.type == BT_CLASS && expr->ts.type == BT_DERIVED)
+      if (cm->ts.type == BT_CLASS)
 	{
 	  tmp = gfc_class_data_get (dest);
 	  tmp = build_fold_indirect_ref_loc (input_location, tmp);
@@ -9005,7 +9017,6 @@ gfc_trans_subcomponent_assign (tree dest, gfc_component * cm,
       /* For deferred strings insert a memcpy.  */
       if (cm->ts.type == BT_CHARACTER && cm->ts.deferred)
 	{
-	  tree size;
 	  gcc_assert (se.string_length || expr->ts.u.cl->backend_decl);
 	  size = size_of_string_in_bytes (cm->ts.kind, se.string_length
 						? se.string_length
@@ -9013,6 +9024,29 @@ gfc_trans_subcomponent_assign (tree dest, gfc_component * cm,
 	  tmp = gfc_build_memcpy_call (tmp, se.expr, size);
 	  gfc_add_expr_to_block (&block, tmp);
 	}
+      else if (cm->ts.type == BT_CLASS)
+	{
+	  /* Fix the expression for memcpy.  */
+	  if (expr->expr_type != EXPR_VARIABLE)
+	    se.expr = gfc_evaluate_now (se.expr, &block);
+
+	  if (expr->ts.type == BT_CHARACTER)
+	    size = fold_convert (size_type_node, se.string_length);
+	  else
+	    size = TYPE_SIZE_UNIT (gfc_typenode_for_spec (&expr->ts));
+
+	  /* Now copy the expression to the constructor component _data.  */
+	  gfc_add_expr_to_block (&block,
+				 gfc_build_memcpy_call (tmp, se.expr, size));
+
+	  /* Fill the unlimited polymorphic _len field.  */
+	  if (UNLIMITED_POLY (cm))
+	    {
+	      tmp = gfc_class_len_get (gfc_get_class_from_expr (tmp));
+	      gfc_add_modify (&block, tmp,
+			      fold_convert (TREE_TYPE (tmp), size));
+	    }
+	}
       else
 	gfc_add_modify (&block, tmp,
 			fold_convert (TREE_TYPE (tmp), se.expr));

[-- Attachment #3: pr49213.f90 --]
[-- Type: text/x-fortran, Size: 1893 bytes --]

! { dg-do run }
!
! Contributed by Neil Carlson  <neil.n.carlson@gmail.com>
!
program main
  character(2) :: c

  type :: S
    integer :: n
  end type
  type(S) :: Sobj

  type, extends(S) :: S2
    integer :: m
  end type
  type(S2) :: S2obj

  type :: T
    class(S), allocatable :: x
  end type
  type(T) :: Tobj

  Sobj = S(1)
  Tobj = T(Sobj)

  S2obj = S2(1,2)
  Tobj = T(S2obj)            ! Failed here
  select type (x => Tobj%x)
    type is (S2)
      if ((x%n .ne. 1) .or. (x%m .ne. 2)) stop 1
    class default
      stop 2
  end select

  c = "  "
  call pass_it (T(Sobj))
  if (c .ne. "S ") stop 3
  call pass_it (T(S2obj))    ! and here
  if (c .ne. "S2") stop 4

  call bar

contains

  subroutine pass_it (foo)
    type(T), intent(in) :: foo
    select type (x => foo%x)
      type is (S)
        c = "S "
        if (x%n .ne. 1) stop 5
      type is (S2)
        c = "S2"
        if ((x%n .ne. 1) .or. (x%m .ne. 2)) stop 6
      class default
        stop 7
    end select
  end subroutine

  subroutine bar
   ! Test from comment #29 of the PR - due to Janus Weil
    type tContainer
      class(*), allocatable :: x
    end type
    integer, parameter :: i = 0
    character(7) :: chr = "goodbye"
    type(tContainer) :: cont

    cont%x = i ! linker error: undefined reference to `__copy_INTEGER_4_.3804'

    cont = tContainer(i+42) ! Failed here
    select type (z => cont%x)
      type is (integer)
        if (z .ne. 42) stop 8
      class default
        stop 9
    end select

    cont = tContainer('hello!')
    select type (z => cont%x)
      type is (character(*))
        if (z .ne. 'hello!') stop 10
      class default
        stop 11
    end select

    cont = tContainer(chr)
    select type (z => cont%x)
      type is (character(*))
        if (z .ne. 'goodbye') stop 12
      class default
        stop 13
    end select

  end subroutine bar
end program

Re: [Patch, fortran] PR49213 - [OOP] gfortran rejects structure constructor expression

[Harald Anlauf]

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Hi Paul!

On 6/24/23 15:18, Paul Richard Thomas via Gcc-patches wrote:
> I have included the adjustment to 'gfc_is_ptr_fcn' and eliminating the
> extra blank line, introduced by my last patch. I played safe and went
> exclusively for class functions with attr.class_pointer set on the
> grounds that these have had all the accoutrements checked and built
> (ie. class_ok). I am still not sure if this is necessary or not.

maybe it is my fault, but I find the version in the patch confusing:

@@ -816,7 +816,7 @@ bool
  gfc_is_ptr_fcn (gfc_expr *e)
  {
    return e != NULL && e->expr_type == EXPR_FUNCTION
-             && (gfc_expr_attr (e).pointer
+             && ((e->ts.type != BT_CLASS && gfc_expr_attr (e).pointer)
                   || (e->ts.type == BT_CLASS
                       && CLASS_DATA (e)->attr.class_pointer));
  }

The caller 'gfc_is_ptr_fcn' has e->expr_type == EXPR_FUNCTION, so
gfc_expr_attr (e) boils down to:

       if (e->value.function.esym && e->value.function.esym->result)
	{
	  gfc_symbol *sym = e->value.function.esym->result;
	  attr = sym->attr;
	  if (sym->ts.type == BT_CLASS && sym->attr.class_ok)
	    {
	      attr.dimension = CLASS_DATA (sym)->attr.dimension;
	      attr.pointer = CLASS_DATA (sym)->attr.class_pointer;
	      attr.allocatable = CLASS_DATA (sym)->attr.allocatable;
	    }
	}
...
       else if (e->symtree)
	attr = gfc_variable_attr (e, NULL);

So I thought this should already do what you want if you do

gfc_is_ptr_fcn (gfc_expr *e)
{
   return e != NULL && e->expr_type == EXPR_FUNCTION && gfc_expr_attr
(e).pointer;
}

or what am I missing?  The additional checks in gfc_expr_attr are
there to avoid ICEs in case CLASS_DATA (sym) has issues, and we all
know Gerhard who showed that he is an expert in exploiting this.

To sum up, I'd prefer to use the safer form if it works.  If it
doesn't, I would expect a latent issue.

The rest of the code looked good to me, but I was suspicious about
the handling of CHARACTER.

Nasty as I am, I modified the testcase to use character(kind=4)
instead of kind=1 (see attached).  This either fails here (stop 10),
or if I activate the marked line

!    cont = tContainer('hello!')       ! ### ICE! ###

I get an ICE.

Can you have another look?

Thanks,
Harald

>

> OK for trunk?
>
> Paul
>
> Fortran: Enable class expressions in structure constructors [PR49213]
>
> 2023-06-24  Paul Thomas  <pault@gcc.gnu.org>
>
> gcc/fortran
> PR fortran/49213
> * expr.cc (gfc_is_ptr_fcn): Guard pointer attribute to exclude
> class expressions.
> * resolve.cc (resolve_assoc_var): Call gfc_is_ptr_fcn to allow
> associate names with pointer function targets to be used in
> variable definition context.
> * trans-decl.cc (get_symbol_decl): Remove extraneous line.
> * trans-expr.cc (alloc_scalar_allocatable_subcomponent): Obtain
> size of intrinsic and character expressions.
> (gfc_trans_subcomponent_assign): Expand assignment to class
> components to include intrinsic and character expressions.
>
> gcc/testsuite/
> PR fortran/49213
> * gfortran.dg/pr49213.f90 : New test

[-- Attachment #2: pr49213-kind4.f90 --]
[-- Type: text/x-fortran, Size: 2013 bytes --]

! { dg-do run }
!
! Contributed by Neil Carlson  <neil.n.carlson@gmail.com>
!
program main
! character(2) :: c
  character(2,kind=4) :: c

  type :: S
    integer :: n
  end type
  type(S) :: Sobj

  type, extends(S) :: S2
    integer :: m
  end type
  type(S2) :: S2obj

  type :: T
    class(S), allocatable :: x
  end type
  type(T) :: Tobj

  Sobj = S(1)
  Tobj = T(Sobj)

  S2obj = S2(1,2)
  Tobj = T(S2obj)            ! Failed here
  select type (x => Tobj%x)
    type is (S2)
      if ((x%n .ne. 1) .or. (x%m .ne. 2)) stop 1
    class default
      stop 2
  end select

  c = 4_"  "
  call pass_it (T(Sobj))
  if (c .ne. 4_"S ") stop 3
  call pass_it (T(S2obj))    ! and here
  if (c .ne. 4_"S2") stop 4

  call bar

contains

  subroutine pass_it (foo)
    type(T), intent(in) :: foo
    select type (x => foo%x)
      type is (S)
        c = 4_"S "
        if (x%n .ne. 1) stop 5
      type is (S2)
        c = 4_"S2"
        if ((x%n .ne. 1) .or. (x%m .ne. 2)) stop 6
      class default
        stop 7
    end select
  end subroutine

  subroutine bar
   ! Test from comment #29 of the PR - due to Janus Weil
    type tContainer
      class(*), allocatable :: x
    end type
    integer, parameter :: i = 0
    character(7,kind=4) :: chr = 4_"goodbye"
    type(tContainer) :: cont

    cont%x = i ! linker error: undefined reference to `__copy_INTEGER_4_.3804'

    cont = tContainer(i+42) ! Failed here
    select type (z => cont%x)
      type is (integer)
        if (z .ne. 42) stop 8
      class default
        stop 9
    end select

!    cont = tContainer('hello!')       ! ### ICE! ###
    cont = tContainer(4_'hello!')
    select type (z => cont%x)
      type is (character(*,kind=4))
        if (z .ne. 4_'hello!') stop 10
      class default
        stop 11
    end select

    cont = tContainer(chr)
    select type (z => cont%x)
      type is (character(*,kind=4))
        if (z .ne. 4_'goodbye') stop 12
      class default
        stop 13
    end select

  end subroutine bar
end program

Re: [Patch, fortran] PR49213 - [OOP] gfortran rejects structure constructor expression

[Paul Richard Thomas]

Hi Harald,

I feel very foolish! You are absolutely right about gfc_is_ptr_fcn
(gfc_expr *e). I never checked what gfc_expr_attr did here.

I have fixed character (kind=4) but have now run into trouble with
expressions such as cont = tContainer(sqrt (2.0_8)). I think that
simplification is being missed somewhere.

I'm onto it.

Paul

On Sat, 24 Jun 2023 at 20:50, Harald Anlauf <anlauf@gmx.de> wrote:
>
> Hi Paul!
>
> On 6/24/23 15:18, Paul Richard Thomas via Gcc-patches wrote:
> > I have included the adjustment to 'gfc_is_ptr_fcn' and eliminating the
> > extra blank line, introduced by my last patch. I played safe and went
> > exclusively for class functions with attr.class_pointer set on the
> > grounds that these have had all the accoutrements checked and built
> > (ie. class_ok). I am still not sure if this is necessary or not.
>
> maybe it is my fault, but I find the version in the patch confusing:
>
> @@ -816,7 +816,7 @@ bool
>   gfc_is_ptr_fcn (gfc_expr *e)
>   {
>     return e != NULL && e->expr_type == EXPR_FUNCTION
> -             && (gfc_expr_attr (e).pointer
> +             && ((e->ts.type != BT_CLASS && gfc_expr_attr (e).pointer)
>                    || (e->ts.type == BT_CLASS
>                        && CLASS_DATA (e)->attr.class_pointer));
>   }
>
> The caller 'gfc_is_ptr_fcn' has e->expr_type == EXPR_FUNCTION, so
> gfc_expr_attr (e) boils down to:
>
>        if (e->value.function.esym && e->value.function.esym->result)
>         {
>           gfc_symbol *sym = e->value.function.esym->result;
>           attr = sym->attr;
>           if (sym->ts.type == BT_CLASS && sym->attr.class_ok)
>             {
>               attr.dimension = CLASS_DATA (sym)->attr.dimension;
>               attr.pointer = CLASS_DATA (sym)->attr.class_pointer;
>               attr.allocatable = CLASS_DATA (sym)->attr.allocatable;
>             }
>         }
> ...
>        else if (e->symtree)
>         attr = gfc_variable_attr (e, NULL);
>
> So I thought this should already do what you want if you do
>
> gfc_is_ptr_fcn (gfc_expr *e)
> {
>    return e != NULL && e->expr_type == EXPR_FUNCTION && gfc_expr_attr
> (e).pointer;
> }
>
> or what am I missing?  The additional checks in gfc_expr_attr are
> there to avoid ICEs in case CLASS_DATA (sym) has issues, and we all
> know Gerhard who showed that he is an expert in exploiting this.
>
> To sum up, I'd prefer to use the safer form if it works.  If it
> doesn't, I would expect a latent issue.
>
> The rest of the code looked good to me, but I was suspicious about
> the handling of CHARACTER.
>
> Nasty as I am, I modified the testcase to use character(kind=4)
> instead of kind=1 (see attached).  This either fails here (stop 10),
> or if I activate the marked line
>
> !    cont = tContainer('hello!')       ! ### ICE! ###
>
> I get an ICE.
>
> Can you have another look?
>
> Thanks,
> Harald
>
> >
>
> > OK for trunk?
> >
> > Paul
> >
> > Fortran: Enable class expressions in structure constructors [PR49213]
> >
> > 2023-06-24  Paul Thomas  <pault@gcc.gnu.org>
> >
> > gcc/fortran
> > PR fortran/49213
> > * expr.cc (gfc_is_ptr_fcn): Guard pointer attribute to exclude
> > class expressions.
> > * resolve.cc (resolve_assoc_var): Call gfc_is_ptr_fcn to allow
> > associate names with pointer function targets to be used in
> > variable definition context.
> > * trans-decl.cc (get_symbol_decl): Remove extraneous line.
> > * trans-expr.cc (alloc_scalar_allocatable_subcomponent): Obtain
> > size of intrinsic and character expressions.
> > (gfc_trans_subcomponent_assign): Expand assignment to class
> > components to include intrinsic and character expressions.
> >
> > gcc/testsuite/
> > PR fortran/49213
> > * gfortran.dg/pr49213.f90 : New test



-- 
"If you can't explain it simply, you don't understand it well enough"
- Albert Einstein

Re: [Patch, fortran] PR49213 - [OOP] gfortran rejects structure constructor expression

[Paul Richard Thomas]

[-- Attachment #1: Type: text/plain, Size: 4267 bytes --]

Hi Harald,

Let's try again :-)

OK for trunk?

Regards

Paul

Fortran: Enable class expressions in structure constructors [PR49213]

2023-06-27  Paul Thomas  <pault@gcc.gnu.org>

gcc/fortran
PR fortran/49213
* expr.cc (gfc_is_ptr_fcn): Remove reference to class_pointer.
* resolve.cc (resolve_assoc_var): Call gfc_is_ptr_fcn to allow
associate names with pointer function targets to be used in
variable definition context.
* trans-decl.cc (get_symbol_decl): Remove extraneous line.
* trans-expr.cc (alloc_scalar_allocatable_subcomponent): Obtain
size of intrinsic and character expressions.
(gfc_trans_subcomponent_assign): Expand assignment to class
components to include intrinsic and character expressions.

gcc/testsuite/
PR fortran/49213
* gfortran.dg/pr49213.f90 : New test

On Sat, 24 Jun 2023 at 20:50, Harald Anlauf <anlauf@gmx.de> wrote:
>
> Hi Paul!
>
> On 6/24/23 15:18, Paul Richard Thomas via Gcc-patches wrote:
> > I have included the adjustment to 'gfc_is_ptr_fcn' and eliminating the
> > extra blank line, introduced by my last patch. I played safe and went
> > exclusively for class functions with attr.class_pointer set on the
> > grounds that these have had all the accoutrements checked and built
> > (ie. class_ok). I am still not sure if this is necessary or not.
>
> maybe it is my fault, but I find the version in the patch confusing:
>
> @@ -816,7 +816,7 @@ bool
>   gfc_is_ptr_fcn (gfc_expr *e)
>   {
>     return e != NULL && e->expr_type == EXPR_FUNCTION
> -             && (gfc_expr_attr (e).pointer
> +             && ((e->ts.type != BT_CLASS && gfc_expr_attr (e).pointer)
>                    || (e->ts.type == BT_CLASS
>                        && CLASS_DATA (e)->attr.class_pointer));
>   }
>
> The caller 'gfc_is_ptr_fcn' has e->expr_type == EXPR_FUNCTION, so
> gfc_expr_attr (e) boils down to:
>
>        if (e->value.function.esym && e->value.function.esym->result)
>         {
>           gfc_symbol *sym = e->value.function.esym->result;
>           attr = sym->attr;
>           if (sym->ts.type == BT_CLASS && sym->attr.class_ok)
>             {
>               attr.dimension = CLASS_DATA (sym)->attr.dimension;
>               attr.pointer = CLASS_DATA (sym)->attr.class_pointer;
>               attr.allocatable = CLASS_DATA (sym)->attr.allocatable;
>             }
>         }
> ...
>        else if (e->symtree)
>         attr = gfc_variable_attr (e, NULL);
>
> So I thought this should already do what you want if you do
>
> gfc_is_ptr_fcn (gfc_expr *e)
> {
>    return e != NULL && e->expr_type == EXPR_FUNCTION && gfc_expr_attr
> (e).pointer;
> }
>
> or what am I missing?  The additional checks in gfc_expr_attr are
> there to avoid ICEs in case CLASS_DATA (sym) has issues, and we all
> know Gerhard who showed that he is an expert in exploiting this.
>
> To sum up, I'd prefer to use the safer form if it works.  If it
> doesn't, I would expect a latent issue.
>
> The rest of the code looked good to me, but I was suspicious about
> the handling of CHARACTER.
>
> Nasty as I am, I modified the testcase to use character(kind=4)
> instead of kind=1 (see attached).  This either fails here (stop 10),
> or if I activate the marked line
>
> !    cont = tContainer('hello!')       ! ### ICE! ###
>
> I get an ICE.
>
> Can you have another look?
>
> Thanks,
> Harald
>
> >
>
> > OK for trunk?
> >
> > Paul
> >
> > Fortran: Enable class expressions in structure constructors [PR49213]
> >
> > 2023-06-24  Paul Thomas  <pault@gcc.gnu.org>
> >
> > gcc/fortran
> > PR fortran/49213
> > * expr.cc (gfc_is_ptr_fcn): Guard pointer attribute to exclude
> > class expressions.
> > * resolve.cc (resolve_assoc_var): Call gfc_is_ptr_fcn to allow
> > associate names with pointer function targets to be used in
> > variable definition context.
> > * trans-decl.cc (get_symbol_decl): Remove extraneous line.
> > * trans-expr.cc (alloc_scalar_allocatable_subcomponent): Obtain
> > size of intrinsic and character expressions.
> > (gfc_trans_subcomponent_assign): Expand assignment to class
> > components to include intrinsic and character expressions.
> >
> > gcc/testsuite/
> > PR fortran/49213
> > * gfortran.dg/pr49213.f90 : New test



-- 
"If you can't explain it simply, you don't understand it well enough"
- Albert Einstein

[-- Attachment #2: pr49213.f90 --]
[-- Type: text/x-fortran, Size: 2252 bytes --]

! { dg-do run }
!
! Contributed by Neil Carlson  <neil.n.carlson@gmail.com>
!
program main
  character(2) :: c

  type :: S
    integer :: n
  end type
  type(S) :: Sobj

  type, extends(S) :: S2
    integer :: m
  end type
  type(S2) :: S2obj

  type :: T
    class(S), allocatable :: x
  end type

  type tContainer
    class(*), allocatable :: x
  end type

  type(T) :: Tobj

  Sobj = S(1)
  Tobj = T(Sobj)

  S2obj = S2(1,2)
  Tobj = T(S2obj)            ! Failed here
  select type (x => Tobj%x)
    type is (S2)
      if ((x%n .ne. 1) .or. (x%m .ne. 2)) stop 1
    class default
      stop 2
  end select

  c = "  "
  call pass_it (T(Sobj))
  if (c .ne. "S ") stop 3
  call pass_it (T(S2obj))    ! and here
  if (c .ne. "S2") stop 4

  call bar

contains

  subroutine pass_it (foo)
    type(T), intent(in) :: foo
    select type (x => foo%x)
      type is (S)
        c = "S "
        if (x%n .ne. 1) stop 5
      type is (S2)
        c = "S2"
        if ((x%n .ne. 1) .or. (x%m .ne. 2)) stop 6
      class default
        stop 7
    end select
  end subroutine

  subroutine check_it (t, errno)
    type(tContainer)  :: t
    integer :: errno
    select type (x => t%x)
      type is (integer)
        if (x .ne. 42) stop errno
      type is (integer(8))
        if (x .ne. 42_8) stop errno
      type is (real(8))
        if (int(x**2) .ne. 2) stop errno
      type is (character(*, kind=1))
        if (x .ne. "end of tests") stop errno
      type is (character(*, kind=4))
        if ((x .ne. 4_"hello!") .and. (x .ne. 4_"goodbye")) stop errno
       class default
        stop errno
    end select
  end subroutine

  subroutine bar
   ! Test from comment #29 extended by Harald Anlauf to check kinds /= default
    integer(8), parameter :: i = 0_8
    integer :: j = 42
    character(7,kind=4) :: chr4 = 4_"goodbye"
    type(tContainer) :: cont

    cont%x = j
    call check_it (cont, 8)

    cont = tContainer(i+42_8)
    call check_it (cont, 9)

    cont = tContainer(sqrt (2.0_8))
    call check_it (cont, 10)

    cont = tContainer(4_"hello!")
    call check_it (cont, 11)

    cont = tContainer(chr4)
    call check_it (cont, 12)

    cont = tContainer("end of tests")
    call check_it (cont, 13)

  end subroutine bar
end program

[-- Attachment #3: pr49213.diff --]
[-- Type: text/x-patch, Size: 5560 bytes --]

diff --git a/gcc/fortran/expr.cc b/gcc/fortran/expr.cc
index c960dfeabd9..e418f1f3301 100644
--- a/gcc/fortran/expr.cc
+++ b/gcc/fortran/expr.cc
@@ -816,9 +816,7 @@ bool
 gfc_is_ptr_fcn (gfc_expr *e)
 {
   return e != NULL && e->expr_type == EXPR_FUNCTION
-	      && (gfc_expr_attr (e).pointer
-		  || (e->ts.type == BT_CLASS
-		      && CLASS_DATA (e)->attr.class_pointer));
+	      && gfc_expr_attr (e).pointer;
 }
 
 
diff --git a/gcc/fortran/resolve.cc b/gcc/fortran/resolve.cc
index 82e6ac53aa1..8e018b6e7e8 100644
--- a/gcc/fortran/resolve.cc
+++ b/gcc/fortran/resolve.cc
@@ -1350,6 +1350,9 @@ resolve_structure_cons (gfc_expr *expr, int init)
 	  && CLASS_DATA (comp)->as)
  	rank = CLASS_DATA (comp)->as->rank;
 
+      if (comp->ts.type == BT_CLASS && cons->expr->ts.type != BT_CLASS)
+	  gfc_find_vtab (&cons->expr->ts);
+
       if (cons->expr->expr_type != EXPR_NULL && rank != cons->expr->rank
 	  && (comp->attr.allocatable || cons->expr->rank))
 	{
@@ -1381,7 +1384,7 @@ resolve_structure_cons (gfc_expr *expr, int init)
 			 gfc_basic_typename (comp->ts.type));
 	      t = false;
 	    }
-	  else
+	  else if (!UNLIMITED_POLY (comp))
 	    {
 	      bool t2 = gfc_convert_type (cons->expr, &comp->ts, 1);
 	      if (t)
diff --git a/gcc/fortran/trans-decl.cc b/gcc/fortran/trans-decl.cc
index 18589e17843..b0fd25e92a3 100644
--- a/gcc/fortran/trans-decl.cc
+++ b/gcc/fortran/trans-decl.cc
@@ -1915,7 +1915,6 @@ gfc_get_symbol_decl (gfc_symbol * sym)
 	gcc_assert (!sym->value || sym->value->expr_type == EXPR_NULL);
     }
 
-
   gfc_finish_var_decl (decl, sym);
 
   if (sym->ts.type == BT_CHARACTER)
diff --git a/gcc/fortran/trans-expr.cc b/gcc/fortran/trans-expr.cc
index 3c209bcde97..b292b5f8995 100644
--- a/gcc/fortran/trans-expr.cc
+++ b/gcc/fortran/trans-expr.cc
@@ -8781,6 +8781,7 @@ alloc_scalar_allocatable_subcomponent (stmtblock_t *block, tree comp,
   tree size;
   tree size_in_bytes;
   tree lhs_cl_size = NULL_TREE;
+  gfc_se se;
 
   if (!comp)
     return;
@@ -8815,16 +8816,30 @@ alloc_scalar_allocatable_subcomponent (stmtblock_t *block, tree comp,
     }
   else if (cm->ts.type == BT_CLASS)
     {
-      gcc_assert (expr2->ts.type == BT_CLASS || expr2->ts.type == BT_DERIVED);
-      if (expr2->ts.type == BT_DERIVED)
+      if (expr2->ts.type != BT_CLASS)
 	{
-	  tmp = gfc_get_symbol_decl (expr2->ts.u.derived);
-	  size = TYPE_SIZE_UNIT (tmp);
+	  if (expr2->ts.type == BT_CHARACTER)
+	    {
+	      gfc_init_se (&se, NULL);
+	      gfc_conv_expr (&se, expr2);
+	      size = build_int_cst (gfc_array_index_type, expr2->ts.kind);
+	      size = fold_build2_loc (input_location, MULT_EXPR,
+				      gfc_array_index_type,
+				      se.string_length, size);
+	      size = fold_convert (size_type_node, size);
+	    }
+	  else
+	    {
+	      if (expr2->ts.type == BT_DERIVED)
+		tmp = gfc_get_symbol_decl (expr2->ts.u.derived);
+	      else
+		tmp = gfc_typenode_for_spec (&expr2->ts);
+	      size = TYPE_SIZE_UNIT (tmp);
+	    }
 	}
       else
 	{
 	  gfc_expr *e2vtab;
-	  gfc_se se;
 	  e2vtab = gfc_find_and_cut_at_last_class_ref (expr2);
 	  gfc_add_vptr_component (e2vtab);
 	  gfc_add_size_component (e2vtab);
@@ -8975,6 +8990,7 @@ gfc_trans_subcomponent_assign (tree dest, gfc_component * cm,
     {
       gfc_init_se (&se, NULL);
       gfc_conv_expr (&se, expr);
+      tree size;
 
       /* Take care about non-array allocatable components here.  The alloc_*
 	 routine below is motivated by the alloc_scalar_allocatable_for_
@@ -8990,7 +9006,7 @@ gfc_trans_subcomponent_assign (tree dest, gfc_component * cm,
 	  && expr->symtree->n.sym->attr.dummy)
 	se.expr = build_fold_indirect_ref_loc (input_location, se.expr);
 
-      if (cm->ts.type == BT_CLASS && expr->ts.type == BT_DERIVED)
+      if (cm->ts.type == BT_CLASS)
 	{
 	  tmp = gfc_class_data_get (dest);
 	  tmp = build_fold_indirect_ref_loc (input_location, tmp);
@@ -9005,7 +9021,6 @@ gfc_trans_subcomponent_assign (tree dest, gfc_component * cm,
       /* For deferred strings insert a memcpy.  */
       if (cm->ts.type == BT_CHARACTER && cm->ts.deferred)
 	{
-	  tree size;
 	  gcc_assert (se.string_length || expr->ts.u.cl->backend_decl);
 	  size = size_of_string_in_bytes (cm->ts.kind, se.string_length
 						? se.string_length
@@ -9013,6 +9028,36 @@ gfc_trans_subcomponent_assign (tree dest, gfc_component * cm,
 	  tmp = gfc_build_memcpy_call (tmp, se.expr, size);
 	  gfc_add_expr_to_block (&block, tmp);
 	}
+      else if (cm->ts.type == BT_CLASS)
+	{
+	  /* Fix the expression for memcpy.  */
+	  if (expr->expr_type != EXPR_VARIABLE)
+	    se.expr = gfc_evaluate_now (se.expr, &block);
+
+	  if (expr->ts.type == BT_CHARACTER)
+	    {
+	      size = build_int_cst (gfc_array_index_type, expr->ts.kind);
+	      size = fold_build2_loc (input_location, MULT_EXPR,
+				      gfc_array_index_type,
+				      se.string_length, size);
+	      size = fold_convert (size_type_node, size);
+	    }
+	  else
+	    size = TYPE_SIZE_UNIT (gfc_typenode_for_spec (&expr->ts));
+
+	  /* Now copy the expression to the constructor component _data.  */
+	  gfc_add_expr_to_block (&block,
+				 gfc_build_memcpy_call (tmp, se.expr, size));
+
+	  /* Fill the unlimited polymorphic _len field.  */
+	  if (UNLIMITED_POLY (cm) && expr->ts.type == BT_CHARACTER)
+	    {
+	      tmp = gfc_class_len_get (gfc_get_class_from_expr (tmp));
+	      gfc_add_modify (&block, tmp,
+			      fold_convert (TREE_TYPE (tmp),
+			      se.string_length));
+	    }
+	}
       else
 	gfc_add_modify (&block, tmp,
 			fold_convert (TREE_TYPE (tmp), se.expr));

Re: [Patch, fortran] PR49213 - [OOP] gfortran rejects structure constructor expression

[Harald Anlauf]

Hi Paul,

this is much better now.

I have only a minor comment left: in the calculation of the
size of a character string you are using an intermediate
gfc_array_index_type, whereas I have learned to use
gfc_charlen_type_node now, which seems like the natural
type here.

OK for trunk, and thanks for your patience!

Harald


On 6/27/23 12:30, Paul Richard Thomas via Gcc-patches wrote:
> Hi Harald,
>
> Let's try again :-)
>
> OK for trunk?
>
> Regards
>
> Paul
>
> Fortran: Enable class expressions in structure constructors [PR49213]
>
> 2023-06-27  Paul Thomas  <pault@gcc.gnu.org>
>
> gcc/fortran
> PR fortran/49213
> * expr.cc (gfc_is_ptr_fcn): Remove reference to class_pointer.
> * resolve.cc (resolve_assoc_var): Call gfc_is_ptr_fcn to allow
> associate names with pointer function targets to be used in
> variable definition context.
> * trans-decl.cc (get_symbol_decl): Remove extraneous line.
> * trans-expr.cc (alloc_scalar_allocatable_subcomponent): Obtain
> size of intrinsic and character expressions.
> (gfc_trans_subcomponent_assign): Expand assignment to class
> components to include intrinsic and character expressions.
>
> gcc/testsuite/
> PR fortran/49213
> * gfortran.dg/pr49213.f90 : New test
>
> On Sat, 24 Jun 2023 at 20:50, Harald Anlauf <anlauf@gmx.de> wrote:
>>
>> Hi Paul!
>>
>> On 6/24/23 15:18, Paul Richard Thomas via Gcc-patches wrote:
>>> I have included the adjustment to 'gfc_is_ptr_fcn' and eliminating the
>>> extra blank line, introduced by my last patch. I played safe and went
>>> exclusively for class functions with attr.class_pointer set on the
>>> grounds that these have had all the accoutrements checked and built
>>> (ie. class_ok). I am still not sure if this is necessary or not.
>>
>> maybe it is my fault, but I find the version in the patch confusing:
>>
>> @@ -816,7 +816,7 @@ bool
>>    gfc_is_ptr_fcn (gfc_expr *e)
>>    {
>>      return e != NULL && e->expr_type == EXPR_FUNCTION
>> -             && (gfc_expr_attr (e).pointer
>> +             && ((e->ts.type != BT_CLASS && gfc_expr_attr (e).pointer)
>>                     || (e->ts.type == BT_CLASS
>>                         && CLASS_DATA (e)->attr.class_pointer));
>>    }
>>
>> The caller 'gfc_is_ptr_fcn' has e->expr_type == EXPR_FUNCTION, so
>> gfc_expr_attr (e) boils down to:
>>
>>         if (e->value.function.esym && e->value.function.esym->result)
>>          {
>>            gfc_symbol *sym = e->value.function.esym->result;
>>            attr = sym->attr;
>>            if (sym->ts.type == BT_CLASS && sym->attr.class_ok)
>>              {
>>                attr.dimension = CLASS_DATA (sym)->attr.dimension;
>>                attr.pointer = CLASS_DATA (sym)->attr.class_pointer;
>>                attr.allocatable = CLASS_DATA (sym)->attr.allocatable;
>>              }
>>          }
>> ...
>>         else if (e->symtree)
>>          attr = gfc_variable_attr (e, NULL);
>>
>> So I thought this should already do what you want if you do
>>
>> gfc_is_ptr_fcn (gfc_expr *e)
>> {
>>     return e != NULL && e->expr_type == EXPR_FUNCTION && gfc_expr_attr
>> (e).pointer;
>> }
>>
>> or what am I missing?  The additional checks in gfc_expr_attr are
>> there to avoid ICEs in case CLASS_DATA (sym) has issues, and we all
>> know Gerhard who showed that he is an expert in exploiting this.
>>
>> To sum up, I'd prefer to use the safer form if it works.  If it
>> doesn't, I would expect a latent issue.
>>
>> The rest of the code looked good to me, but I was suspicious about
>> the handling of CHARACTER.
>>
>> Nasty as I am, I modified the testcase to use character(kind=4)
>> instead of kind=1 (see attached).  This either fails here (stop 10),
>> or if I activate the marked line
>>
>> !    cont = tContainer('hello!')       ! ### ICE! ###
>>
>> I get an ICE.
>>
>> Can you have another look?
>>
>> Thanks,
>> Harald
>>
>>>
>>
>>> OK for trunk?
>>>
>>> Paul
>>>
>>> Fortran: Enable class expressions in structure constructors [PR49213]
>>>
>>> 2023-06-24  Paul Thomas  <pault@gcc.gnu.org>
>>>
>>> gcc/fortran
>>> PR fortran/49213
>>> * expr.cc (gfc_is_ptr_fcn): Guard pointer attribute to exclude
>>> class expressions.
>>> * resolve.cc (resolve_assoc_var): Call gfc_is_ptr_fcn to allow
>>> associate names with pointer function targets to be used in
>>> variable definition context.
>>> * trans-decl.cc (get_symbol_decl): Remove extraneous line.
>>> * trans-expr.cc (alloc_scalar_allocatable_subcomponent): Obtain
>>> size of intrinsic and character expressions.
>>> (gfc_trans_subcomponent_assign): Expand assignment to class
>>> components to include intrinsic and character expressions.
>>>
>>> gcc/testsuite/
>>> PR fortran/49213
>>> * gfortran.dg/pr49213.f90 : New test
>
>
>

Re: [Patch, fortran] PR49213 - [OOP] gfortran rejects structure constructor expression

[Paul Richard Thomas]

Hi Harald,

I'll change to gfc_charlen_type_node.

Thanks for your patience in reviewing this patch :-)

Cheers

Paul

On Tue, 27 Jun 2023 at 20:27, Harald Anlauf <anlauf@gmx.de> wrote:
>
> Hi Paul,
>
> this is much better now.
>
> I have only a minor comment left: in the calculation of the
> size of a character string you are using an intermediate
> gfc_array_index_type, whereas I have learned to use
> gfc_charlen_type_node now, which seems like the natural
> type here.
>
> OK for trunk, and thanks for your patience!
>
> Harald
>
>
> On 6/27/23 12:30, Paul Richard Thomas via Gcc-patches wrote:
> > Hi Harald,
> >
> > Let's try again :-)
> >
> > OK for trunk?
> >
> > Regards
> >
> > Paul
> >
> > Fortran: Enable class expressions in structure constructors [PR49213]
> >
> > 2023-06-27  Paul Thomas  <pault@gcc.gnu.org>
> >
> > gcc/fortran
> > PR fortran/49213
> > * expr.cc (gfc_is_ptr_fcn): Remove reference to class_pointer.
> > * resolve.cc (resolve_assoc_var): Call gfc_is_ptr_fcn to allow
> > associate names with pointer function targets to be used in
> > variable definition context.
> > * trans-decl.cc (get_symbol_decl): Remove extraneous line.
> > * trans-expr.cc (alloc_scalar_allocatable_subcomponent): Obtain
> > size of intrinsic and character expressions.
> > (gfc_trans_subcomponent_assign): Expand assignment to class
> > components to include intrinsic and character expressions.
> >
> > gcc/testsuite/
> > PR fortran/49213
> > * gfortran.dg/pr49213.f90 : New test
> >
> > On Sat, 24 Jun 2023 at 20:50, Harald Anlauf <anlauf@gmx.de> wrote:
> >>
> >> Hi Paul!
> >>
> >> On 6/24/23 15:18, Paul Richard Thomas via Gcc-patches wrote:
> >>> I have included the adjustment to 'gfc_is_ptr_fcn' and eliminating the
> >>> extra blank line, introduced by my last patch. I played safe and went
> >>> exclusively for class functions with attr.class_pointer set on the
> >>> grounds that these have had all the accoutrements checked and built
> >>> (ie. class_ok). I am still not sure if this is necessary or not.
> >>
> >> maybe it is my fault, but I find the version in the patch confusing:
> >>
> >> @@ -816,7 +816,7 @@ bool
> >>    gfc_is_ptr_fcn (gfc_expr *e)
> >>    {
> >>      return e != NULL && e->expr_type == EXPR_FUNCTION
> >> -             && (gfc_expr_attr (e).pointer
> >> +             && ((e->ts.type != BT_CLASS && gfc_expr_attr (e).pointer)
> >>                     || (e->ts.type == BT_CLASS
> >>                         && CLASS_DATA (e)->attr.class_pointer));
> >>    }
> >>
> >> The caller 'gfc_is_ptr_fcn' has e->expr_type == EXPR_FUNCTION, so
> >> gfc_expr_attr (e) boils down to:
> >>
> >>         if (e->value.function.esym && e->value.function.esym->result)
> >>          {
> >>            gfc_symbol *sym = e->value.function.esym->result;
> >>            attr = sym->attr;
> >>            if (sym->ts.type == BT_CLASS && sym->attr.class_ok)
> >>              {
> >>                attr.dimension = CLASS_DATA (sym)->attr.dimension;
> >>                attr.pointer = CLASS_DATA (sym)->attr.class_pointer;
> >>                attr.allocatable = CLASS_DATA (sym)->attr.allocatable;
> >>              }
> >>          }
> >> ...
> >>         else if (e->symtree)
> >>          attr = gfc_variable_attr (e, NULL);
> >>
> >> So I thought this should already do what you want if you do
> >>
> >> gfc_is_ptr_fcn (gfc_expr *e)
> >> {
> >>     return e != NULL && e->expr_type == EXPR_FUNCTION && gfc_expr_attr
> >> (e).pointer;
> >> }
> >>
> >> or what am I missing?  The additional checks in gfc_expr_attr are
> >> there to avoid ICEs in case CLASS_DATA (sym) has issues, and we all
> >> know Gerhard who showed that he is an expert in exploiting this.
> >>
> >> To sum up, I'd prefer to use the safer form if it works.  If it
> >> doesn't, I would expect a latent issue.
> >>
> >> The rest of the code looked good to me, but I was suspicious about
> >> the handling of CHARACTER.
> >>
> >> Nasty as I am, I modified the testcase to use character(kind=4)
> >> instead of kind=1 (see attached).  This either fails here (stop 10),
> >> or if I activate the marked line
> >>
> >> !    cont = tContainer('hello!')       ! ### ICE! ###
> >>
> >> I get an ICE.
> >>
> >> Can you have another look?
> >>
> >> Thanks,
> >> Harald
> >>
> >>>
> >>
> >>> OK for trunk?
> >>>
> >>> Paul
> >>>
> >>> Fortran: Enable class expressions in structure constructors [PR49213]
> >>>
> >>> 2023-06-24  Paul Thomas  <pault@gcc.gnu.org>
> >>>
> >>> gcc/fortran
> >>> PR fortran/49213
> >>> * expr.cc (gfc_is_ptr_fcn): Guard pointer attribute to exclude
> >>> class expressions.
> >>> * resolve.cc (resolve_assoc_var): Call gfc_is_ptr_fcn to allow
> >>> associate names with pointer function targets to be used in
> >>> variable definition context.
> >>> * trans-decl.cc (get_symbol_decl): Remove extraneous line.
> >>> * trans-expr.cc (alloc_scalar_allocatable_subcomponent): Obtain
> >>> size of intrinsic and character expressions.
> >>> (gfc_trans_subcomponent_assign): Expand assignment to class
> >>> components to include intrinsic and character expressions.
> >>>
> >>> gcc/testsuite/
> >>> PR fortran/49213
> >>> * gfortran.dg/pr49213.f90 : New test
> >
> >
> >
>


-- 
"If you can't explain it simply, you don't understand it well enough"
- Albert Einstein