diff --git a/Eigen/src/SparseLU/SparseLU_gemm_kernel.h b/Eigen/src/SparseLU/SparseLU_gemm_kernel.h
index 11e7318b5..293857bf8 100644
--- a/Eigen/src/SparseLU/SparseLU_gemm_kernel.h
+++ b/Eigen/src/SparseLU/SparseLU_gemm_kernel.h
@@ -93,8 +93,16 @@ void sparselu_gemm(int m, int n, int d, const Scalar* A, int lda, const Scalar*
         
                   a0 = pload<Packet>(A0);
                   a1 = pload<Packet>(A1);
-        if(RK==4) a2 = pload<Packet>(A2);
-        if(RK==4) a3 = pload<Packet>(A3);
+        if(RK==4)
+        {
+          a2 = pload<Packet>(A2);
+          a3 = pload<Packet>(A3);
+        }
+        else
+        {
+          // workaround "may be used uninitialized in this function" warning
+          a2 = a3 = a0;
+        }
         
 #define KMADD(c, a, b, tmp) tmp = b; tmp = pmul(a,tmp); c = padd(c,tmp);
 #define WORK(I)  \
@@ -137,6 +145,7 @@ void sparselu_gemm(int m, int n, int d, const Scalar* A, int lda, const Scalar*
         {
           WORK(0);
         }
+#undef WORK
         // process the remaining rows without vectorization
         for(int i=actual_b_end2; i<actual_b; ++i)
         {
@@ -154,7 +163,6 @@ void sparselu_gemm(int m, int n, int d, const Scalar* A, int lda, const Scalar*
         
         Bc0 += RK;
         Bc1 += RK;
-#undef WORK
       } // peeled loop on k
     } // peeled loop on the columns j
     // process the last column (we now perform a matrux-vector product)
diff --git a/test/sparse_basic.cpp b/test/sparse_basic.cpp
index cebb5e6a0..798716887 100644
--- a/test/sparse_basic.cpp
+++ b/test/sparse_basic.cpp
@@ -449,6 +449,7 @@ void test_sparse_basic()
 {
   for(int i = 0; i < g_repeat; i++) {
     int s = Eigen::internal::random<int>(1,50);
+    EIGEN_UNUSED_VARIABLE(s);
     CALL_SUBTEST_1(( sparse_basic(SparseMatrix<double>(8, 8)) ));
     CALL_SUBTEST_2(( sparse_basic(SparseMatrix<std::complex<double>, ColMajor>(s, s)) ));
     CALL_SUBTEST_2(( sparse_basic(SparseMatrix<std::complex<double>, RowMajor>(s, s)) ));
diff --git a/test/unalignedcount.cpp b/test/unalignedcount.cpp
index 5451159e6..ca7e159f3 100644
--- a/test/unalignedcount.cpp
+++ b/test/unalignedcount.cpp
@@ -40,5 +40,7 @@ void test_unalignedcount()
   #else
   // The following line is to eliminate "variable not used" warnings
   nb_load = nb_loadu = nb_store = nb_storeu = 0;
+  int a(0), b(0);
+  VERIFY(a==b);
   #endif
 }