From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752901AbaBQVLx (ORCPT ); Mon, 17 Feb 2014 16:11:53 -0500 Received: from mail-pb0-f41.google.com ([209.85.160.41]:54803 "EHLO mail-pb0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752141AbaBQVLw convert rfc822-to-8bit (ORCPT ); Mon, 17 Feb 2014 16:11:52 -0500 MIME-Version: 1.0 In-Reply-To: <530279EC.5010605@infradead.org> References: <530279EC.5010605@infradead.org> Date: Mon, 17 Feb 2014 22:11:51 +0100 X-Google-Sender-Auth: duVr9hzNd_oNpJJNJ9GU807Fyv8 Message-ID: Subject: Re: New bcache compiler warning (was: Re: bcache: Minor fixes from kbuild robot) From: Geert Uytterhoeven To: Randy Dunlap Cc: Kent Overstreet , Linux Kernel Mailing List , linux-bcache@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Feb 17, 2014 at 10:06 PM, Randy Dunlap wrote: > On 02/17/2014 01:00 PM, Geert Uytterhoeven wrote: >> On Fri, Feb 14, 2014 at 8:04 PM, Linux Kernel Mailing List >> wrote: >>> bcache: Minor fixes from kbuild robot >> >>> diff --git a/drivers/md/bcache/bset.c b/drivers/md/bcache/bset.c >>> index 4f6b594..3f74b4b 100644 >>> --- a/drivers/md/bcache/bset.c >>> +++ b/drivers/md/bcache/bset.c >>> @@ -23,7 +23,7 @@ void bch_dump_bset(struct btree_keys *b, struct bset *i, unsigned set) >>> for (k = i->start; k < bset_bkey_last(i); k = next) { >>> next = bkey_next(k); >>> >>> - printk(KERN_ERR "block %u key %zi/%u: ", set, >>> + printk(KERN_ERR "block %u key %li/%u: ", set, >>> (uint64_t *) k - i->d, i->keys); >>> >>> if (b->ops->key_dump) >> >> On 32-bit (m68k): >> drivers/md/bcache/bset.c: In function ‘bch_dump_bset’: >> drivers/md/bcache/bset.c:27: warning: format ‘%li’ expects type ‘long >> int’, but argument 3 has type ‘int’ >> >> What are you trying to print here? It looks a bit strange to me. >> Technically, the difference between two pointers is of type ptrdiff_. >> The kernel had >> >> typedef __kernel_ptrdiff_t ptrdiff_t; >> >> and >> >> #if __BITS_PER_LONG != 64 >> typedef unsigned int __kernel_size_t; >> typedef int __kernel_ssize_t; >> typedef int __kernel_ptrdiff_t; >> #else >> typedef __kernel_ulong_t __kernel_size_t; >> typedef __kernel_long_t __kernel_ssize_t; >> typedef __kernel_long_t __kernel_ptrdiff_t; >> #endif >> >> So I'd expect "%zi" to be the right way, and a quick test compile on >> 32-bit (m68k) >> and 64-bit (amd64) comfirms that. What was wrong with it? > > The kernel supports 't' (%t) for ptrdiff_t (same as glibc), > so %ti should work (or %tu). Yes, that compiles without warnings, too. And after more decyphering, "(uint64_t *) k - i->d" seems to be positive, so "%tu" should be OK. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds