Print correct info if CLPF unit tests fail.

Change-Id: Ieac27194f342d8ef9ef98c96ebea9d0c444658cf
diff --git a/test/clpf_test.cc b/test/clpf_test.cc
index 608a8ca..74a41a8 100644
--- a/test/clpf_test.cc
+++ b/test/clpf_test.cc
@@ -139,6 +139,7 @@
     }
   }
 
+  pos--;
   EXPECT_EQ(0, error)
       << "Error: ClpfBlockTest, SIMD and C mismatch." << std::endl
       << "First error at " << pos % size << "," << pos / size << " ("