diff --git a/examples/modules.cpp b/examples/modules.cpp
index 1a908082..68d7abe6 100644
--- a/examples/modules.cpp
+++ b/examples/modules.cpp
@@ -1,7 +1,8 @@
-import libremidi;
-
-#include <cstdlib>
 #include <iostream>
+#include <cstdio>
+#include <iomanip>
+
+import libremidi;
 
 inline std::ostream& operator<<(std::ostream& s, const libremidi::message& message)
 {
diff --git a/include/libremidi/detail/semaphore.hpp b/include/libremidi/detail/semaphore.hpp
index 8cc0c565..e4034bc7 100644
--- a/include/libremidi/detail/semaphore.hpp
+++ b/include/libremidi/detail/semaphore.hpp
@@ -12,7 +12,7 @@ struct semaphore_pair_lock
 
     // FIXME if jack is not running we can skip this
     this->sem_needpost.release();
-    this->sem_cleanup.try_acquire_for(1s);
+    (void)this->sem_cleanup.try_acquire_for(1s);
   }
 
   void check_client_released()