I figured out the problem. it _was_ visual studio. When I fire up the program in a debug build, sometimes, for an unknown reason the console needs me to press any key for the code to continue executing. It usually happens before the SFML window is created. This time it was happening on the first SQL query execution. My guess is the console sometimes gets stuck in the "press any key to close this window" trigger, and needs to be activated so the std::cerr message can be displayed, before executing the next lines of code (even though a new instance of the program is run so exiting the console is no longer an active option)