Al Viro wrote: > On Tue, Jul 24, 2007 at 12:13:19PM -0700, Jeremy Fitzhardinge wrote: > >> Al Viro wrote: >> >>> Works here... >>> >>> >> Hm, doesn't here: >> >> CC arch/i386/kernel/irq.o >> /home/jeremy/hg/xen/paravirt/linux/arch/i386/kernel/irq.c: In function >> '__BUG': >> include2/asm/bug.h:29: warning: 'noreturn' function does return >> >> This is with current FC7 distro gcc: gcc version 4.1.2 20070502 (Red Hat >> 4.1.2-12) >> > > Interesting... Looks like it's both version- and flags-dependent. > Oh, well... > > BTW, alpha, frv, m68k and s390 have BUG() that is not recognized as > noreturn by gcc. >
Yes, it was something I added because I thought it would be useful. Traditionally, BUG has not affected gcc's control flow analysis. The other option is trying to use __builtin_trap, which happens to generate ud2a on i386. But I don't think its necessarily guaranteed to always do that, and I don't know if it does anything useful for other architectures. J - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/