Description Resource Path Location Type fatal error: usb_cdc.h: No such file or directory usbcfg.c /ARMCM4-STM32F407-DISCOVERY-PI line 23 C/C++ Problem
I can´t find usb_cdc.h in the directories. So I think something changes???
The USB stuff has been changed with version 2.6. It's correct that there's no usb_cdc.h file anymore. Take a look at the demos to see how it's done now (The code itself changed too [slightly]).
That warning is known ad accepted, you can suppress that by putting a "return 0" at the end but doing so the Keil and IAR compiler would start complaining about unreachable code.
Being 2 compilers vs 1 compiler Keil and IAR win and the warning using GCC has to stay.