Fix crash if we exit lib table setup

Fixes https://gitlab.com/kicad/code/kicad/-/issues/16917

cvpcb/cvpcb.cpp

@@ -219,6 +219,9 @@ bool IFACE::OnKifaceStart( PGM_BASE* aProgram, int aCtlBits, KIWAY* aKiway )
     }
     catch( const IO_ERROR& ioe )
     {
+        // we didnt get anywhere deregister the settings
+        aProgram->GetSettingsManager().FlushAndRelease( KifaceSettings(), false );
+
         DisplayErrorMessage( nullptr, _( "An error occurred attempting to load the global "
                                          "footprint library table." ),
                              ioe.What() );

eeschema/eeschema.cpp

@@ -381,7 +381,8 @@ bool IFACE::OnKifaceStart( PGM_BASE* aProgram, int aCtlBits, KIWAY* aKiway )
 
     // Register the symbol editor settings as well because they share a KiFACE and need to be
     // loaded prior to use to avoid threading deadlocks
-    aProgram->GetSettingsManager().RegisterSettings( new SYMBOL_EDITOR_SETTINGS );
+    SYMBOL_EDITOR_SETTINGS* symSettings = new SYMBOL_EDITOR_SETTINGS();
+    aProgram->GetSettingsManager().RegisterSettings( symSettings ); // manager takes ownership
 
     // We intentionally register KifaceSettings after SYMBOL_EDITOR_SETTINGS
     // In legacy configs, many settings were in a single editor config nd the migration routine
@@ -392,7 +393,12 @@ bool IFACE::OnKifaceStart( PGM_BASE* aProgram, int aCtlBits, KIWAY* aKiway )
     start_common( aCtlBits );
 
     if( !loadGlobalLibTable() )
+    {
+        // we didnt get anywhere deregister the settings
+        aProgram->GetSettingsManager().FlushAndRelease( symSettings, false );
+        aProgram->GetSettingsManager().FlushAndRelease( KifaceSettings(), false );
         return false;
+    }
 
     m_jobHandler = std::make_unique<EESCHEMA_JOBS_HANDLER>( aKiway );
 

pcbnew/pcbnew.cpp

@@ -414,7 +414,21 @@ bool IFACE::OnKifaceStart( PGM_BASE* aProgram, int aCtlBits, KIWAY* aKiway )
     start_common( aCtlBits );
 
     if( !loadGlobalLibTable() )
+    {
+        // we didnt get anywhere deregister the
+        aProgram->GetSettingsManager().FlushAndRelease(
+                aProgram->GetSettingsManager().GetAppSettings<CVPCB_SETTINGS>(), false );
+
+        aProgram->GetSettingsManager().FlushAndRelease( KifaceSettings(), false );
+
+        aProgram->GetSettingsManager().FlushAndRelease(
+                aProgram->GetSettingsManager().GetAppSettings<FOOTPRINT_EDITOR_SETTINGS>(), false );
+
+        aProgram->GetSettingsManager().FlushAndRelease(
+                aProgram->GetSettingsManager().GetAppSettings<EDA_3D_VIEWER_SETTINGS>(), false );
+
         return false;
+    }
 
     m_jobHandler = std::make_unique<PCBNEW_JOBS_HANDLER>( aKiway );