Program crashes

[Fallen_]

Hi, when calling this:

std::string final = tmp.substr(tmp.find(" "), tmp.length());
		m_chan = new Channel(this, QString(final.c_str()), socket);
		tabs->addTab(m_chan, QString(final.c_str()));

std::string final = tmp.substr(tmp.find(" "), tmp.length());
		m_chan = new Channel(this, QString(final.c_str()), socket);
		tabs->addTab(m_chan, QString(final.c_str()));

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the program crahes without a reason. im sure the tmp has a " "
PS:
when i debug i get seg fault