Fix broken build

include/spdlog/details/mpmc_blocking_q.h

@@ -30,12 +30,6 @@ public:
     {
     }
 
-    size_t overrun_counter() const
-    {
-      std::unique_lock<std::mutex> lock(queue_mutex_);
-      return q_.overrun_counter();
-    }
-
 #ifndef __MINGW32__
     // try to enqueue and block if no room left
     void enqueue(T &&item)
@@ -111,6 +105,12 @@ public:
 
 #endif
 
+    size_t overrun_counter()
+    {
+        std::unique_lock<std::mutex> lock(queue_mutex_);
+        return q_.overrun_counter();
+    }
+
 private:
     std::mutex queue_mutex_;
     std::condition_variable push_cv_;

include/spdlog/details/thread_pool.h

@@ -157,7 +157,7 @@ public:
         post_async_msg_(async_msg(std::move(worker_ptr), async_msg_type::flush), overflow_policy);
     }
 
-    size_t overrun_counter() const
+    size_t overrun_counter()
     {
         return q_.overrun_counter();
     }