re PR fortran/77596 ([F03] procedure pointer component with implicit interface…

re PR fortran/77596 ([F03] procedure pointer component with implicit interface can point to a function)

2016-11-08  Janus Weil  <janus@gcc.gnu.org>

	PR fortran/77596
	* expr.c (gfc_check_pointer_assign): Add special check for procedure-
	pointer component with absent interface.

2016-11-08  Janus Weil  <janus@gcc.gnu.org>

	PR fortran/77596
	* gfortran.dg/proc_ptr_comp_46.f90: New test.

From-SVN: r241972

gcc/fortran/ChangeLog

+2016-11-08  Janus Weil  <janus@gcc.gnu.org>
+
+	PR fortran/77596
+	* expr.c (gfc_check_pointer_assign): Add special check for procedure-
+	pointer component with absent interface.
+
 2016-11-07  Thomas Koenig  <tkoenig@gcc.gnu.org>
 
 	PR fortran/78226

gcc/fortran/expr.c

@@ -3445,7 +3445,7 @@ gfc_check_pointer_assign (gfc_expr *lvalue, gfc_expr *rvalue)
     {
       char err[200];
       gfc_symbol *s1,*s2;
-      gfc_component *comp;
+      gfc_component *comp1, *comp2;
       const char *name;
 
       attr = gfc_expr_attr (rvalue);
@@ -3549,9 +3549,9 @@ gfc_check_pointer_assign (gfc_expr *lvalue, gfc_expr *rvalue)
 	    }
 	}
 
-      comp = gfc_get_proc_ptr_comp (lvalue);
-      if (comp)
-	s1 = comp->ts.interface;
+      comp1 = gfc_get_proc_ptr_comp (lvalue);
+      if (comp1)
+	s1 = comp1->ts.interface;
       else
 	{
 	  s1 = lvalue->symtree->n.sym;
@@ -3559,18 +3559,18 @@ gfc_check_pointer_assign (gfc_expr *lvalue, gfc_expr *rvalue)
 	    s1 = s1->ts.interface;
 	}
 
-      comp = gfc_get_proc_ptr_comp (rvalue);
-      if (comp)
+      comp2 = gfc_get_proc_ptr_comp (rvalue);
+      if (comp2)
 	{
 	  if (rvalue->expr_type == EXPR_FUNCTION)
 	    {
-	      s2 = comp->ts.interface->result;
+	      s2 = comp2->ts.interface->result;
 	      name = s2->name;
 	    }
 	  else
 	    {
-	      s2 = comp->ts.interface;
-	      name = comp->name;
+	      s2 = comp2->ts.interface;
+	      name = comp2->name;
 	    }
 	}
       else if (rvalue->expr_type == EXPR_FUNCTION)
@@ -3591,6 +3591,15 @@ gfc_check_pointer_assign (gfc_expr *lvalue, gfc_expr *rvalue)
       if (s2 && s2->attr.proc_pointer && s2->ts.interface)
 	s2 = s2->ts.interface;
 
+      /* Special check for the case of absent interface on the lvalue.
+       * All other interface checks are done below. */
+      if (!s1 && comp1 && comp1->attr.subroutine && s2 && s2->attr.function)
+	{
+	  gfc_error ("Interface mismatch in procedure pointer assignment "
+		     "at %L: '%s' is not a subroutine", &rvalue->where, name);
+	  return false;
+	}
+
       if (s1 == s2 || !s1 || !s2)
 	return true;
 

gcc/testsuite/ChangeLog

+2016-11-08  Janus Weil  <janus@gcc.gnu.org>
+
+	PR fortran/77596
+	* gfortran.dg/proc_ptr_comp_46.f90: New test.
+
 2016-11-08  Bin Cheng  <bin.cheng@arm.com>
 
 	* gcc.dg/vect/pr56541.c: Xfail on !vect_cond_mixed targets.

gcc/testsuite/gfortran.dg/proc_ptr_comp_46.f90

+! { dg-do compile }
+!
+! PR 77596: [F03] procedure pointer component with implicit interface can point to a function
+!
+! Contributed by toK <t.kondic@leeds.ac.uk>
+
+program xxx
+  implicit none
+
+  type tf
+     procedure(), nopass, pointer :: fp
+  end type tf
+
+  call ass()
+
+contains
+
+  integer function ff(x)
+    integer, intent(in) :: x
+    ff = x + 1
+  end function ff
+
+  subroutine ass()
+    type(tf) :: p
+    p%fp=>ff        ! { dg-error "is not a subroutine" }
+    call p%fp(3)
+  end subroutine ass
+
+end