Bug fix for Qt GUI when closing ROM while the emulation thread is haning on a breakpoint. Now the thread is allowed to complete its frame so that it is idle with a minimal call stack before the ROM is closed. This prevents the emulation thread from coming out of its breakpoint wait loop at attempting to continue running its frame with no ROM data loaded. This fixes a segmentation fault crash that was mentioned in the project Qt issues thread.

src/drivers/Qt/ConsoleDebugger.cpp

@@ -76,6 +76,7 @@ static std::list <ConsoleDebugger*> dbgWinList;
 
 static void DeleteBreak(int sel);
 static bool waitingAtBp = false;
+static bool bpDebugEnable = true;
 static int  lastBpIdx   = 0;
 //----------------------------------------------------------------------------
 ConsoleDebugger::ConsoleDebugger(QWidget *parent)
@@ -2565,11 +2566,16 @@ void ConsoleDebugger::vbarChanged(int value)
 	asmView->setLine( value );
 }
 //----------------------------------------------------------------------------
+void bpDebugSetEnable(bool val)
+{
+	bpDebugEnable = val;
+}
+//----------------------------------------------------------------------------
 void FCEUD_DebugBreakpoint( int bpNum )
 {
 	std::list <ConsoleDebugger*>::iterator it;
 
-	if ( !nes_shm->runEmulator )
+	if ( !nes_shm->runEmulator || !bpDebugEnable )
 	{
 		return;
 	}
@@ -2585,7 +2591,8 @@ void FCEUD_DebugBreakpoint( int bpNum )
 		(*it)->breakPointNotify( bpNum );
 	}
 
-	while ( nes_shm->runEmulator && FCEUI_EmulationPaused() && !FCEUI_EmulationFrameStepped())
+	while ( nes_shm->runEmulator && bpDebugEnable &&
+			FCEUI_EmulationPaused() && !FCEUI_EmulationFrameStepped())
 	{
 		// HACK: break when Frame Advance is pressed
 		extern bool frameAdvanceRequested;
@@ -2617,6 +2624,11 @@ bool debuggerWindowIsOpen(void)
 	return (dbgWinList.size() > 0);
 }
 //----------------------------------------------------------------------------
+bool debuggerWaitingAtBreakpoint(void)
+{
+	return waitingAtBp;
+}
+//----------------------------------------------------------------------------
 void updateAllDebuggerWindows( void )
 {
 	std::list <ConsoleDebugger*>::iterator it;

src/drivers/Qt/ConsoleDebugger.h

@@ -344,6 +344,8 @@ class ConsoleDebugger : public QDialog
 };
 
 bool debuggerWindowIsOpen(void);
+bool debuggerWaitingAtBreakpoint(void);
+void bpDebugSetEnable(bool val);
 void saveGameDebugBreakpoints(void);
 void loadGameDebugBreakpoints(void);
 void debuggerClearAllBreakpoints(void);

src/drivers/Qt/ConsoleWindow.cpp

@@ -48,6 +48,7 @@
 #include "../../input.h"
 #include "../../movie.h"
 #include "../../version.h"
+#include "common/os_utils.h"
 
 #ifdef _S9XLUA_H
 #include "../../fceulua.h"

src/drivers/Qt/fceuWrapper.cpp

@@ -384,6 +384,29 @@ CloseGame(void)
 	if (!isloaded) {
 		return(0);
 	}
+
+	// If the emulation thread is stuck hanging at a breakpoint,
+	// disable breakpoint debugging and wait for the thread to 
+	// complete its frame. So that it is idle with a minimal call
+	// stack when we close the ROM. After thread has completed the
+	// frame, it is then safe to re-enable breakpoint debugging.
+	if ( debuggerWaitingAtBreakpoint() )
+	{
+		bpDebugSetEnable(false);
+
+		if ( fceuWrapperIsLocked() )
+		{
+			fceuWrapperUnLock();
+			msleep(100);
+			fceuWrapperLock();
+		}
+		else
+		{
+			msleep(100);
+		}
+		bpDebugSetEnable(true);
+	}
+
 	hexEditorSaveBookmarks();
 	saveGameDebugBreakpoints();
 	debuggerClearAllBreakpoints();