"dummy write elsewhere definitely..." <- Seems not to be true sadly. ```rust pub fn set_flag_and_reboot() -> ! { critical_section::with(|_| { unsafe { BOOTLOADER_FLAG.get().write(BOOTLOADER_FLAG_VALUE) }; let mut dummy = 0u32; unsafe { ((&mut dummy) as *mut u32).write_volatile(0) }; cortex_m::peripheral::SCB::sys_reset(); }) } ``` I see the write in assembly, but doesn't help. The stack is in the same ram