C++ Quiz: are you a code guru?

Do you think that it is impossible to make silly mistakes in your own code? Developers of PVS-Studio C/C++ static analyzer are inclined to disagree!
Code analyzers work non-stop and can find many bugs which are otherwise hard to notice. Here we've gathered many fragments from well-known open source projects in which static analyzer had found real bugs.
We offer you to compete against PVS-Studio static analyzer by locating bugs in 15 source code fragments randomly selected from our database of open source projects. You get a point for a correct answer if it was given within 60 seconds.