diff --git a/src/unix/threadpsx.cpp b/src/unix/threadpsx.cpp
index ac55f84a1f..d6e805347f 100644
--- a/src/unix/threadpsx.cpp
+++ b/src/unix/threadpsx.cpp
@@ -123,10 +123,10 @@ static wxMutex *gs_mutexDeleteThread = (wxMutex *)NULL;
 // gs_nThreadsBeingDeleted will have been deleted
 static wxCondition *gs_condAllDeleted = (wxCondition *)NULL;
 
-#if wxUSE_GUI
-    // this mutex must be acquired before any call to a GUI function
-    static wxMutex *gs_mutexGui;
-#endif // wxUSE_GUI
+// this mutex must be acquired before any call to a GUI function
+// (it's not inside #if wxUSE_GUI because this file is compiled as part
+// of wxBase)
+static wxMutex *gs_mutexGui = NULL;
 
 // when we wait for a thread to exit, we're blocking on a condition which the
 // thread signals in its SignalExit() method -- but this condition can't be a
@@ -1617,11 +1617,8 @@ bool wxThreadModule::OnInit()
 
     gs_tidMain = pthread_self();
 
-#if wxUSE_GUI
     gs_mutexGui = new wxMutex();
-
     gs_mutexGui->Lock();
-#endif // wxUSE_GUI
 
     gs_mutexDeleteThread = new wxMutex();
     gs_condAllDeleted = new wxCondition( *gs_mutexDeleteThread );
@@ -1666,12 +1663,9 @@ void wxThreadModule::OnExit()
         gs_allThreads[0]->Delete();
     }
 
-#if wxUSE_GUI
     // destroy GUI mutex
     gs_mutexGui->Unlock();
-
     delete gs_mutexGui;
-#endif // wxUSE_GUI
 
     // and free TLD slot
     (void)pthread_key_delete(gs_keySelf);
@@ -1720,16 +1714,12 @@ static void DeleteThread(wxThread *This)
 
 void wxMutexGuiEnter()
 {
-#if wxUSE_GUI
     gs_mutexGui->Lock();
-#endif // wxUSE_GUI
 }
 
 void wxMutexGuiLeave()
 {
-#if wxUSE_GUI
     gs_mutexGui->Unlock();
-#endif // wxUSE_GUI
 }
 
 // ----------------------------------------------------------------------------