diff --git a/gcc/c-family/c-common.h b/gcc/c-family/c-common.h
index 202c8f9..7e857c3 100644
--- a/gcc/c-family/c-common.h
+++ b/gcc/c-family/c-common.h
@@ -1245,7 +1245,7 @@ extern void c_finish_omp_flush (location_t);
 extern void c_finish_omp_taskwait (location_t);
 extern void c_finish_omp_taskyield (location_t);
 extern tree c_finish_omp_for (location_t, enum tree_code, tree, tree, tree,
-			      tree, tree, tree);
+			      tree, tree, tree, tree);
 extern tree c_finish_oacc_wait (location_t, tree, tree);
 extern void c_omp_split_clauses (location_t, enum tree_code, omp_clause_mask,
 				 tree, tree *);
diff --git a/gcc/c-family/c-omp.c b/gcc/c-family/c-omp.c
index f020a80..81aef7a 100644
--- a/gcc/c-family/c-omp.c
+++ b/gcc/c-family/c-omp.c
@@ -432,6 +432,10 @@ c_omp_for_incr_canonicalize_ptr (location_t loc, tree decl, tree incr)
 
 /* Validate and generate OMP_FOR.
    DECLV is a vector of iteration variables, for each collapsed loop.
+
+   ORIG_DECLV, if non-NULL, is a vector with the original iteration
+   variables (prior to any transformations, by say, C++ iterators).
+
    INITV, CONDV and INCRV are vectors containing initialization
    expressions, controlling predicates and increment expressions.
    BODY is the body of the loop and PRE_BODY statements that go before
@@ -439,7 +443,8 @@ c_omp_for_incr_canonicalize_ptr (location_t loc, tree decl, tree incr)
 
 tree
 c_finish_omp_for (location_t locus, enum tree_code code, tree declv,
-		  tree initv, tree condv, tree incrv, tree body, tree pre_body)
+		  tree orig_declv, tree initv, tree condv, tree incrv,
+		  tree body, tree pre_body)
 {
   location_t elocus;
   bool fail = false;
@@ -678,6 +683,7 @@ c_finish_omp_for (location_t locus, enum tree_code code, tree declv,
       OMP_FOR_INCR (t) = incrv;
       OMP_FOR_BODY (t) = body;
       OMP_FOR_PRE_BODY (t) = pre_body;
+      OMP_FOR_ORIG_DECLS (t) = orig_declv;
 
       SET_EXPR_LOCATION (t, locus);
       return add_stmt (t);
diff --git a/gcc/c/c-parser.c b/gcc/c/c-parser.c
index 90486d2..0a42072 100644
--- a/gcc/c/c-parser.c
+++ b/gcc/c/c-parser.c
@@ -13696,7 +13696,7 @@ c_parser_omp_for_loop (location_t loc, c_parser *parser, enum tree_code code,
      an error from the initialization parsing.  */
   if (!fail)
     {
-      stmt = c_finish_omp_for (loc, code, declv, initv, condv,
+      stmt = c_finish_omp_for (loc, code, declv, NULL, initv, condv,
 			       incrv, body, NULL);
       if (stmt)
 	{
diff --git a/gcc/cp/semantics.c b/gcc/cp/semantics.c
index 5e7a94d..5a4638d 100644
--- a/gcc/cp/semantics.c
+++ b/gcc/cp/semantics.c
@@ -7333,6 +7333,7 @@ finish_omp_for (location_t locus, enum tree_code code, tree declv, tree initv,
   if (processing_template_decl)
     orig_incr = make_tree_vec (TREE_VEC_LENGTH (incrv));
 
+  tree orig_declv = copy_node (declv);
   for (i = 0; i < TREE_VEC_LENGTH (declv); )
     {
       decl = TREE_VEC_ELT (declv, i);
@@ -7430,8 +7431,8 @@ finish_omp_for (location_t locus, enum tree_code code, tree declv, tree initv,
   if (code == CILK_FOR && !processing_template_decl)
     block = push_stmt_list ();
 
-  omp_for = c_finish_omp_for (locus, code, declv, initv, condv, incrv,
-			      body, pre_body);
+  omp_for = c_finish_omp_for (locus, code, declv, orig_declv, initv, condv,
+			      incrv, body, pre_body);
 
   if (omp_for == NULL)
     {
diff --git a/gcc/gimplify.c b/gcc/gimplify.c
index 9ba3f37..90df326 100644
--- a/gcc/gimplify.c
+++ b/gcc/gimplify.c
@@ -7311,7 +7311,11 @@ gimplify_omp_for (tree *expr_p, gimple_seq *pre_p)
       gcc_assert (DECL_P (decl));
       gcc_assert (INTEGRAL_TYPE_P (TREE_TYPE (decl))
 		  || POINTER_TYPE_P (TREE_TYPE (decl)));
-      gimplify_omp_ctxp->iter_vars.quick_push (decl);
+      if (OMP_FOR_ORIG_DECLS (for_stmt))
+	gimplify_omp_ctxp->iter_vars.quick_push
+	  (TREE_VEC_ELT (OMP_FOR_ORIG_DECLS (for_stmt), i));
+      else
+	gimplify_omp_ctxp->iter_vars.quick_push (decl);
 
       /* Make sure the iteration variable is private.  */
       tree c = NULL_TREE;
diff --git a/gcc/tree.def b/gcc/tree.def
index 6703b57..5b6624a 100644
--- a/gcc/tree.def
+++ b/gcc/tree.def
@@ -1087,37 +1087,42 @@ DEFTREECODE (OMP_TASK, "omp_task", tcc_statement, 2)
 	from INIT, COND, and INCR that are technically part of the
 	OMP_FOR structured block, but are evaluated before the loop
 	body begins.
+   Operand 6: OMP_FOR_ORIG_DECLS: If non-NULL, list of DECLs initialized
+	in OMP_FOR_INIT.  In some cases, like C++ iterators, the original
+	DECL init has been lost in gimplification and now contains a
+	temporary (D.nnnn).  This list contains the original DECLs in
+	the source.
 
    VAR must be an integer or pointer variable, which is implicitly thread
    private.  N1, N2 and INCR are required to be loop invariant integer
    expressions that are evaluated without any synchronization.
    The evaluation order, frequency of evaluation and side-effects are
    unspecified by the standards.  */
-DEFTREECODE (OMP_FOR, "omp_for", tcc_statement, 6)
+DEFTREECODE (OMP_FOR, "omp_for", tcc_statement, 7)
 
 /* OpenMP - #pragma omp simd [clause1 ... clauseN]
    Operands like for OMP_FOR.  */
-DEFTREECODE (OMP_SIMD, "omp_simd", tcc_statement, 6)
+DEFTREECODE (OMP_SIMD, "omp_simd", tcc_statement, 7)
 
 /* Cilk Plus - #pragma simd [clause1 ... clauseN]
    Operands like for OMP_FOR.  */
-DEFTREECODE (CILK_SIMD, "cilk_simd", tcc_statement, 6)
+DEFTREECODE (CILK_SIMD, "cilk_simd", tcc_statement, 7)
 
 /* Cilk Plus - _Cilk_for (..)
    Operands like for OMP_FOR.  */
-DEFTREECODE (CILK_FOR, "cilk_for", tcc_statement, 6)
+DEFTREECODE (CILK_FOR, "cilk_for", tcc_statement, 7)
 
 /* OpenMP - #pragma omp distribute [clause1 ... clauseN]
    Operands like for OMP_FOR.  */
-DEFTREECODE (OMP_DISTRIBUTE, "omp_distribute", tcc_statement, 6)
+DEFTREECODE (OMP_DISTRIBUTE, "omp_distribute", tcc_statement, 7)
 
 /* OpenMP - #pragma omp taskloop [clause1 ... clauseN]
    Operands like for OMP_FOR.  */
-DEFTREECODE (OMP_TASKLOOP, "omp_taskloop", tcc_statement, 6)
+DEFTREECODE (OMP_TASKLOOP, "omp_taskloop", tcc_statement, 7)
 
 /* OpenMP - #pragma acc loop [clause1 ... clauseN]
    Operands like for OMP_FOR.  */
-DEFTREECODE (OACC_LOOP, "oacc_loop", tcc_statement, 6)
+DEFTREECODE (OACC_LOOP, "oacc_loop", tcc_statement, 7)
 
 /* OpenMP - #pragma omp teams [clause1 ... clauseN]
    Operand 0: OMP_TEAMS_BODY: Teams body.
diff --git a/gcc/tree.h b/gcc/tree.h
index 7ea7a93..282bfac 100644
--- a/gcc/tree.h
+++ b/gcc/tree.h
@@ -1260,6 +1260,7 @@ extern void protected_set_expr_location (tree, location_t);
 #define OMP_FOR_COND(NODE)	   TREE_OPERAND (OMP_LOOP_CHECK (NODE), 3)
 #define OMP_FOR_INCR(NODE)	   TREE_OPERAND (OMP_LOOP_CHECK (NODE), 4)
 #define OMP_FOR_PRE_BODY(NODE)	   TREE_OPERAND (OMP_LOOP_CHECK (NODE), 5)
+#define OMP_FOR_ORIG_DECLS(NODE)   TREE_OPERAND (OMP_LOOP_CHECK (NODE), 6)
 
 #define OMP_SECTIONS_BODY(NODE)    TREE_OPERAND (OMP_SECTIONS_CHECK (NODE), 0)
 #define OMP_SECTIONS_CLAUSES(NODE) TREE_OPERAND (OMP_SECTIONS_CHECK (NODE), 1)
diff --git a/libgomp/testsuite/libgomp.c++/sink-1.C b/libgomp/testsuite/libgomp.c++/sink-1.C
new file mode 100644
index 0000000..c7b3c16
--- /dev/null
+++ b/libgomp/testsuite/libgomp.c++/sink-1.C
@@ -0,0 +1,21 @@
+// { dg-do compile }
+
+// Test that iterators are allowed in ordered loops.
+
+#include <iostream>
+#include <vector>
+
+int main ()
+{
+  std::vector<int> v;
+  for (int i=1; i<=5; i++) v.push_back(i);
+
+  std::vector<int>::const_iterator it;
+
+#pragma omp parallel for ordered(1)
+  for (it = v.begin(); it < v.end(); ++it)
+    {
+#pragma omp ordered depend(sink:it)
+    std::cout << *it << '\n';
+    }
+}
