diff --git a/tdutils/td/utils/WaitFreeHashMap.h b/tdutils/td/utils/WaitFreeHashMap.h
index bf8aa065e..8fe04b24b 100644
--- a/tdutils/td/utils/WaitFreeHashMap.h
+++ b/tdutils/td/utils/WaitFreeHashMap.h
@@ -76,8 +76,8 @@ class WaitFreeHashMap {
   }
 
   // specialization for WaitFreeHashMap<..., unique_ptr<T>>
-  template <typename ReturnT = decltype(ValueT().get())>
-  ReturnT get_pointer(const KeyT &key) {
+  template <class T = ValueT>
+  typename T::element_type *get_pointer(const KeyT &key) {
     auto &storage = get_storage(key);
     auto it = storage.find(key);
     if (it == storage.end()) {
@@ -86,8 +86,8 @@ class WaitFreeHashMap {
     return it->second.get();
   }
 
-  template <typename ReturnT = decltype(static_cast<const ValueT &>(ValueT()).get())>
-  ReturnT get_pointer(const KeyT &key) const {
+  template <class T = ValueT>
+  const typename T::element_type *get_pointer(const KeyT &key) const {
     auto &storage = get_storage(key);
     auto it = storage.find(key);
     if (it == storage.end()) {
diff --git a/tdutils/test/WaitFreeHashMap.cpp b/tdutils/test/WaitFreeHashMap.cpp
index aa202ca1e..2b53e14a2 100644
--- a/tdutils/test/WaitFreeHashMap.cpp
+++ b/tdutils/test/WaitFreeHashMap.cpp
@@ -38,7 +38,7 @@ TEST(WaitFreeHashMap, stress_test) {
         result -= key * 101;
         result -= value;
       });
-      ASSERT_EQ(0, result);
+      ASSERT_EQ(0u, result);
     }
   };