my project is making TF card a Udisk ,I use cubemx generate keil project, when I use AC6 -O0, everything goes fine,I connect USB, the Udisk display , read ,write is OK, but when I set -O1 or -O2, the Udisk won't come out and shows unknown USB device,when I set -O3 is fine,I try to set optimize level group by group , only "Middlewares/USB_Device_Library" -O1 or -O2 cause this problem, I dont know if it is ST USB library problem
