diff --git a/gcc/poly-int.h b/gcc/poly-int.h
index 2bf9d98599f..d085544a57e 100644
--- a/gcc/poly-int.h
+++ b/gcc/poly-int.h
@@ -1178,6 +1178,19 @@ lshift (const poly_int_pod<N, Ca> &a, const Cb &b)
 }
 }
 
+/* Poly version of sext_hwi, with the same interface.  */
+
+template<unsigned int N, typename C>
+inline poly_int<N, HOST_WIDE_INT>
+sext_hwi (const poly_int<N, C> &a, unsigned int precision)
+{
+  poly_int_pod<N, HOST_WIDE_INT> r;
+  for (unsigned int i = 0; i < N; i++)
+    r.coeffs[i] = sext_hwi (a.coeffs[i], precision);
+  return r;
+}
+
+
 /* Return true if a0 + a1 * x might equal b0 + b1 * x for some nonnegative
    integer x.  */
 
diff --git a/gcc/tree-ssa-sccvn.cc b/gcc/tree-ssa-sccvn.cc
index 76587632312..3732d06b0bb 100644
--- a/gcc/tree-ssa-sccvn.cc
+++ b/gcc/tree-ssa-sccvn.cc
@@ -3684,7 +3684,12 @@ vn_reference_lookup (tree op, tree vuse, vn_lookup_kind kind,
 	    break;
 	  off += vro->off;
 	}
-      if (i == operands.length () - 1)
+      if (i == operands.length () - 1
+	  /* Make sure we the offset we accumulated in a 64bit int
+	     fits the address computation carried out in target
+	     offset precision.  */
+	  && (off.coeffs[0]
+	      == sext_hwi (off.coeffs[0], TYPE_PRECISION (sizetype))))
 	{
 	  gcc_assert (operands[i-1].opcode == MEM_REF);
 	  tree ops[2];
@@ -3808,7 +3813,12 @@ vn_reference_insert (tree op, tree result, tree vuse, tree vdef)
 	    break;
 	  off += vro->off;
 	}
-      if (i == operands.length () - 1)
+      if (i == operands.length () - 1
+	  /* Make sure we the offset we accumulated in a 64bit int
+	     fits the address computation carried out in target
+	     offset precision.  */
+	  && (off.coeffs[0]
+	      == sext_hwi (off.coeffs[0], TYPE_PRECISION (sizetype))))
 	{
 	  gcc_assert (operands[i-1].opcode == MEM_REF);
 	  tree ops[2];