https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64953
--- Comment #17 from manuel.reimer at gmx dot de --- I've tried that and unfortunately I still get the errors when connecting my STM32 via USB. So the only solution, available for me, seems to be to add a note to the sourcecode that it has to be built with GCC 4.8. Thank you anyway to everyone who tried to help.
