pleasing homebrew clang

Author: Klaim

libmamba/include/mamba/util/synchronized_value.hpp

@@ -519,7 +519,7 @@ namespace mamba::util
 
         T m_value{};
         mutable M m_mutex{};  // BEWARE: explicit initializers are required to allow
-                              // synchronized_value instances to be `constinit`
+                              // synchronized_value instances to be `constinit` with some compilers
     };
 
     /** Locks all the provided `synchronized_value` objects using `.synchronize` and
@@ -546,7 +546,12 @@ namespace mamba::util
     ///////////////////////////////////////////////////////////////////////////////////////////
 
     template <std::default_initializable T, Mutex M>
-    constexpr synchronized_value<T, M>::synchronized_value() noexcept(std::is_nothrow_default_constructible_v<T>) = default;
+    constexpr synchronized_value<T, M>::synchronized_value(
+    ) noexcept(std::is_nothrow_default_constructible_v<T>)
+    {
+        // NOTE: non-defaulted because of homebrew/clang compiler not liking the defaulted version
+        // for some reason
+    }
 
     template <std::default_initializable T, Mutex M>
     synchronized_value<T, M>::synchronized_value(T value) noexcept