fortran: ICE in gfc_conv_constant_to_tree PR93604

Using a BOZ constant in a structure constructor in a data statement
resulted in an ICE. Output a "BOZ literal constant cannot appear in
a structure constructor" error message instead.

Original patch provided by Steven G. Kargl  <kargl@gcc.gnu.org>.

Test case added later.

gcc/fortran/ChangeLog

	PR fortran/93604
	* decl.c (gfc_match_data) : Check whether the data expression
	is a derived type and is a constructor. If a BOZ constant
	is encountered in the constructor output an error and return
	MATCH_ERROR.

gcc/testsuite/ChangeLog

	PR fortran/93604
	* gfortran.dg/pr93604.f90 : New test.

gcc/fortran/ChangeLog

+2020-02-24  Steven G. Kargl  <kargl@gcc.gnu.org>
+
+	PR fortran/93604
+	* decl.c (gfc_match_data) : Check whether the data expression
+	is a derived type and is a constructor. If a BOZ constant
+	is encountered in the constructor output an error and return
+	MATCH_ERROR.
+
 2020-02-24  Tobias Burnus  <tobias@codesourcery.com>
 
 	PR fortran/93552

gcc/fortran/decl.c

@@ -716,6 +716,22 @@ gfc_match_data (void)
       new_data->next = gfc_current_ns->data;
       gfc_current_ns->data = new_data;
 
+      /* A BOZ literal constant cannot appear in a structure constructor.
+	 Check for that here for a data statement value.  */
+      if (new_data->value->expr->ts.type == BT_DERIVED
+	  && new_data->value->expr->value.constructor)
+	{
+	  gfc_constructor *c;
+	  c = gfc_constructor_first (new_data->value->expr->value.constructor);
+	  for (; c; c = gfc_constructor_next (c))
+	    if (c->expr->ts.type == BT_BOZ)
+	      {
+		gfc_error ("BOZ literal constant at %L cannot appear in a "
+			   "structure constructor", &c->expr->where);
+		return MATCH_ERROR;
+	      }
+	}
+
       if (gfc_match_eos () == MATCH_YES)
 	break;
 

gcc/testsuite/ChangeLog

+2020-02-20  Mark Eggleston  <mark.eggleston@codethink.com>
+
+	PR fortran/93604
+	* gfortran.dg/pr93604.f90 : New test.
+
 2020-02-24  Jakub Jelinek  <jakub@redhat.com>
 
 	P1937R2 - Fixing inconsistencies between const{expr,eval} functions

gcc/testsuite/gfortran.dg/pr93604.f90

+! { dg-do compile }
+
+program p
+   type t
+      integer :: a
+   end type
+   type(t) :: x
+   data x /t(z'1')/ ! { dg-error "cannot appear in a structure constructor" }
+end
+