fix "pure virtual method called" on quit

stepmania/src/arch/MemoryCard/MemoryCardDriverThreaded.cpp

@@ -34,7 +34,7 @@ void MemoryCardDriverThreaded::StartThread()
 	m_threadMemoryCardMount.Create( MountThread_Start, this );
 }
 
-MemoryCardDriverThreaded::~MemoryCardDriverThreaded()
+void MemoryCardDriverThreaded::StopThread()
 {
 	m_bShutdownNextUpdate = true;
 	LOG->Trace( "Shutting down Mount thread..." );
@@ -42,6 +42,15 @@ MemoryCardDriverThreaded::~MemoryCardDriverThreaded()
 	LOG->Trace( "Mount thread shut down." );
 }
 
+MemoryCardDriverThreaded::~MemoryCardDriverThreaded()
+{
+	/* Must call StopThread from the derived destructor.  Otherwise, we can
+	 * call MountThreadDoOneUpdate from the thread after the derived dtor,
+	 * which means that function is now virtual, and we'll crash with "pure
+	 * virtual method called". */
+	ASSERT( !m_threadMemoryCardMount.IsCreated() );
+}
+
 void MemoryCardDriverThreaded::PauseMountingThread()
 {
 	m_mutexPause.Lock();

stepmania/src/arch/MemoryCard/MemoryCardDriverThreaded.h

@@ -42,6 +42,7 @@ private:
 
 protected:
 	void StartThread();	// call this in the derived constructor to start the mounting thread
+	void StopThread(); // call this in the derived desstructor to stop the mounting thread
 	virtual void MountThreadDoOneUpdate() = 0;	// this will get called as fast as possible
 	virtual void Mount( UsbStorageDevice* pDevice, CString sMountPoint ) = 0;
 

stepmania/src/arch/MemoryCard/MemoryCardDriverThreaded_Linux.cpp

@@ -136,6 +136,11 @@ MemoryCardDriverThreaded_Linux::MemoryCardDriverThreaded_Linux()
 	this->StartThread();
 }
 
+MemoryCardDriverThreaded_Linux::~MemoryCardDriverThreaded_Linux()
+{
+	this->StopThread();
+}
+
 void MemoryCardDriverThreaded_Linux::ResetUsbStorage()
 {
 	//

stepmania/src/arch/MemoryCard/MemoryCardDriverThreaded_Linux.h

@@ -7,6 +7,7 @@ class MemoryCardDriverThreaded_Linux : public MemoryCardDriverThreaded
 {
 public:
 	MemoryCardDriverThreaded_Linux();
+	virtual ~MemoryCardDriverThreaded_Linux();
 
 	virtual void Unmount( UsbStorageDevice* pDevice, CString sMountPoint );
 	virtual void Flush( UsbStorageDevice* pDevice );

stepmania/src/arch/MemoryCard/MemoryCardDriverThreaded_Windows.cpp

@@ -18,6 +18,11 @@ MemoryCardDriverThreaded_Windows::MemoryCardDriverThreaded_Windows()
 	StartThread();
 }
 
+MemoryCardDriverThreaded_Windows::~MemoryCardDriverThreaded_Windows()
+{
+	StopThread();
+}
+
 typedef const CString& CCStringRef;
 
 static bool TestReady( CCStringRef sDrive )

stepmania/src/arch/MemoryCard/MemoryCardDriverThreaded_Windows.h

@@ -8,6 +8,7 @@ class MemoryCardDriverThreaded_Windows : public MemoryCardDriverThreaded
 {
 public:
 	MemoryCardDriverThreaded_Windows();
+	virtual ~MemoryCardDriverThreaded_Windows();
 
 	virtual void Unmount( UsbStorageDevice* pDevice, CString sMountPoint );
 	virtual void Flush( UsbStorageDevice* pDevice );