Script context:
Compare.js#413:

Compare.markDifferences = function(newAndMissingIds) {
...
            entity = Compare.doc1.queryEntity(id);
            entity.setColor(new RColor("green"));
            op = new RModifyObjectOperation(entity.data());
            Compare.di1.applyOperation(op);

ECMA code:

         QScriptValue
        REcmaSharedPointerEntity::setColor
        (QScriptContext* context, QScriptEngine* engine) 
        {
            QScriptValue result = engine->undefinedValue();
                    // public function: can be called from ECMA wrapper of ECMA shell:
                    REntity* self = 
                        getSelf("setColor", context);
=>               Q_ASSERT(self!=NULL);              

Stacktrace:

Thread [1] 18673 (Suspended : Signal : SIGABRT:Aborted)	
	__kernel_vsyscall() at 0xffffe424	
	raise() at 0xb4efc8df	
	abort() at 0xb4efe220	
	RMainWindow::messageHandler() at RMainWindow.cpp:63 0x8f3917a	
	qt_message_output() at 0xb5356f65	
	0xb53571ab	
	qFatal() at 0xb53572c9	
	qt_assert() at 0xb5357355	
	REcmaSharedPointerEntity::setColor() at REcmaSharedPointerEntity.cpp:1,360 0x8bc0602	
	0xb6bd813c	
	0xb6ac1f68	
	0xb6a9164c	
	0xa622afd2	
	0xb6a423e3	
	0xb6af06e0	
	0xb6ac201e	
	0xb6be0cd3	
	0xb6be11a9	
	QMetaObject::metacall() at 0xb5478c83	
	QMetaObject::activate() at 0xb5489134	
	<...more frames...>