Fortran: Enable class expressions in structure constructors [PR49213]

2023-06-28  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

4 files changed, 57 insertions, 12 deletions

diff --git a/gcc/fortran/expr.cc b/gcc/fortran/expr.cc
index c960dfe..e418f1f 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 82e6ac5..8e018b6 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 18589e1..b0fd25e 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 63e3cf9..ad0cdf9 100644
--- a/gcc/fortran/trans-expr.cc
+++ b/gcc/fortran/trans-expr.cc
@@ -8805,6 +8805,7 @@ 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;
@@ -8839,16 +8840,30 @@ 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_charlen_type_node, expr2->ts.kind);
+	      size = fold_build2_loc (input_location, MULT_EXPR,
+				      gfc_charlen_type_node,
+				      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);
@@ -8999,6 +9014,7 @@ 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_
@@ -9014,7 +9030,7 @@ 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);
@@ -9029,7 +9045,6 @@ 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
@@ -9037,6 +9052,36 @@ 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_charlen_type_node, expr->ts.kind);
+	      size = fold_build2_loc (input_location, MULT_EXPR,
+				      gfc_charlen_type_node,
+				      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));