diff --git a/include/builder/file_merging_iterator.hpp b/include/builder/file_merging_iterator.hpp
index 301ad77..911bcaa 100644
--- a/include/builder/file_merging_iterator.hpp
+++ b/include/builder/file_merging_iterator.hpp
@@ -94,7 +94,7 @@ struct file_merging_iterator  //
                 m_tree[p] = uint32_t(-1);
                 --m_num_files_to_merge;
             }
-            const T inf = std::numeric_limits<T>::max();
+            const T inf = T::max();
             while (p) {
                 uint64_t is_r_child = (p & 1) == 0;
                 uint32_t i = 0;
@@ -128,7 +128,7 @@ struct file_merging_iterator  //
         uint32_t l = build(2 * p + 1);
         uint32_t r = build(2 * p + 2);
         uint32_t i = 0;
-        const T inf = std::numeric_limits<T>::max();
+        const T inf = T::max();
         T const* ptr_l = (l == uint32_t(-1)) ? &inf : m_iterators[l].begin;
         T const* ptr_r = (r == uint32_t(-1)) ? &inf : m_iterators[r].begin;
         i = (*ptr_l < *ptr_r) ? l : r;
diff --git a/src/dictionary.cpp b/src/dictionary.cpp
index d0838c9..c1b43f7 100644
--- a/src/dictionary.cpp
+++ b/src/dictionary.cpp
@@ -80,11 +80,11 @@ lookup_result dictionary<Kmer, Offsets>::lookup(Kmer uint_kmer,
 template <typename Kmer, typename Offsets>
 bool dictionary<Kmer, Offsets>::is_member(char const* string_kmer,
                                           bool check_reverse_complement) const {
-    return lookup(string_kmer, check_reverse_complement) != constants::invalid_uint64;
+    return lookup(string_kmer, check_reverse_complement).kmer_id != constants::invalid_uint64;
 }
 template <typename Kmer, typename Offsets>
 bool dictionary<Kmer, Offsets>::is_member(Kmer uint_kmer, bool check_reverse_complement) const {
-    return lookup(uint_kmer, check_reverse_complement) != constants::invalid_uint64;
+    return lookup(uint_kmer, check_reverse_complement).kmer_id != constants::invalid_uint64;
 }
 
 template <typename Kmer, typename Offsets>