fix missing ::type in observer_ptr

diff --git a/src/util/observer_ptr.h b/src/util/observer_ptr.h
index 39f33c9733e9533d5055a237c9374e033ab8c525..85c1fe89b34b1184095ee7e3d5987fc100b5d8f3 100644 (file)
--- a/src/util/observer_ptr.h
+++ b/src/util/observer_ptr.h
@@ -80,7 +80,7 @@ public:
     {
         return value != nullptr;
     }
-    constexpr typename std::add_lvalue_reference<T> operator*() const noexcept
+    constexpr typename std::add_lvalue_reference<T>::type operator*() const noexcept
     {
         return *value;
     }