re PR fortran/56477 (ICE on invalid with pointer assignment to function result)

fortran/
	PR fortran/56477
	* expr.c (gfc_check_pointer_assign): Avoid NULL pointer dereference.

testsuite/
	PR fortran/56477
	* gfortran.dg/pointer_check_13.f90: New test.

From-SVN: r196417

gcc/fortran/ChangeLog

 2013-03-03  Mikael Morin  <mikael@gcc.gnu.org>
 
+	PR fortran/56477
+	* expr.c (gfc_check_pointer_assign): Avoid NULL pointer dereference.
+
+2013-03-03  Mikael Morin  <mikael@gcc.gnu.org>
+
 	PR fortran/54730
 	* array.c (gfc_match_array_constructor): Set a checkpoint before
 	matching a typespec.  Drop it on success, restore it otherwise.

gcc/fortran/expr.c

@@ -3732,7 +3732,7 @@ gfc_check_pointer_assign (gfc_expr *lvalue, gfc_expr *rvalue)
 	  && rvalue->symtree->n.sym->ns->proc_name->attr.flavor != FL_PROCEDURE
 	  && rvalue->symtree->n.sym->ns->proc_name->attr.flavor != FL_PROGRAM)
        for (ns = rvalue->symtree->n.sym->ns;
-	    ns->proc_name && ns->proc_name->attr.flavor != FL_PROCEDURE;
+	    ns && ns->proc_name && ns->proc_name->attr.flavor != FL_PROCEDURE;
 	    ns = ns->parent)
 	if (ns->parent == lvalue->symtree->n.sym->ns)
 	  warn = true;

gcc/testsuite/ChangeLog

 2013-03-03  Mikael Morin  <mikael@gcc.gnu.org>
 
+	PR fortran/56477
+	* gfortran.dg/pointer_check_13.f90: New test.
+
+2013-03-03  Mikael Morin  <mikael@gcc.gnu.org>
+
 	PR fortran/54730
 	* gfortran.dg/array_constructor_42.f90: New test.
 

gcc/testsuite/gfortran.dg/pointer_check_13.f90

+! { dg-do compile }
+! { dg-options "-Wall -Wno-uninitialized" }
+!
+! PR fortran/56477
+! The pointer target live range checking code used to trigger a NULL pointer
+! dereference with the following case.
+!
+! Contributed by Andrew Benson <abensonca@gmail.com>
+!
+module s
+contains
+  function so()
+    implicit none
+    integer, target  :: so
+    integer, pointer :: sp
+    sp => so
+    return
+  end function So
+end module s