2010-03-14  Tobias Burnus  <burnus@net-b.de>

	PR fortran/43362
	* resolve.c (resolve_ordinary_assign): Add check to avoid segfault.

	* gfortran.dg/impure_constructor_1.f90: New test.

--- gcc/fortran/resolve.c	(revision 157446)
+++ gcc/fortran/resolve.c	(revision 157447)
@@ -6640,6 +6640,7 @@ resolve_ordinary_assign (gfc_code *code,
       if (lhs->ts.type == BT_DERIVED
 	    && lhs->expr_type == EXPR_VARIABLE
 	    && lhs->ts.derived->attr.pointer_comp
+	    && rhs->expr_type == EXPR_VARIABLE
 	    && gfc_impure_variable (rhs->symtree->n.sym))
 	{
 	  gfc_error ("The impure variable at %L is assigned to "
--- gcc/testsuite/gfortran.dg/impure_constructor_1.f90	(revision 0)
+++ gcc/testsuite/gfortran.dg/impure_constructor_1.f90	(revision 157447)
@@ -0,0 +1,30 @@
+! { dg-do compile }
+!
+! PR fortran/43362
+!
+module m
+  implicit none
+  type t
+    integer, pointer :: a
+  end type t
+  type t2
+    type(t) :: b
+  end type t2
+  type t3
+    type(t), pointer :: b
+  end type t3
+contains
+ pure subroutine foo(x)
+   type(t), target, intent(in) :: x
+   type(t2) :: y
+   type(t3) :: z
+
+   ! The following gave an ICE but is valid:
+   y = t2(x) ! Note: F2003, C1272 (3) and (4) do not apply
+   
+   ! Variant which is invalid as C1272 (3) applies
+   z = t3(x) ! { dg-error "Invalid expression in the derived type constructor" "" { xfail *-*-* } }
+ end subroutine foo
+end module m
+
+