Hello everyone, I just compiled the kernel by passing "-Wformat-signedness" flag https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html -Wformat-signedness: If -Wformat is specified, also warn if the format string requires an unsigned argument and the argument is signed and vice versa. Now, the C standard says: "If a conversion specification is invalid, the behavior is undefined. If any argument is not the correct type for the corresponding conversion specification, the behavior is *undefined*." For eg: drivers/iio/trigger/stm32-timer-trigger.c:228:24: warning: format ‘%d’ expects argument of type ‘int’, but argument 3 has type ‘unsigned int’ [-Wformat=] return sprintf(buf, "%d\n", (unsigned int)freq); ~^ ~~~~~~~~~~~~~~~~~~ %d What is the rationale for not including/using this flag in the HOSTCFLAGS in the Makefile ? -- Thanks Himanshu Jha