From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnaldo Carvalho de Melo Subject: Re: compile breakage due to [SK_BUFF]: Convert skb->end to sk_buff_data_t Date: Sun, 13 May 2007 20:27:35 -0300 Message-ID: <46479EE7.1030100@redhat.com> References: <200704271703.l3RH3i2F021726@hera.kernel.org> <20070513182941.GC4343@rhun.haifa.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: David Miller , netdev To: Muli Ben-Yehuda Return-path: Received: from mx1.redhat.com ([66.187.233.31]:36428 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756218AbXEMX2E (ORCPT ); Sun, 13 May 2007 19:28:04 -0400 In-Reply-To: <20070513182941.GC4343@rhun.haifa.ibm.com> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Muli Ben-Yehuda wrote: > On Fri, Apr 27, 2007 at 05:03:44PM +0000, Linux Kernel Mailing List wrote: > > >> Gitweb: http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=4305b541357ddbd205aa145dc378926b7cb12283 >> Commit: 4305b541357ddbd205aa145dc378926b7cb12283 >> Parent: 27a884dc3cb63b93c2b3b643f5b31eed5f8a4d26 >> Author: Arnaldo Carvalho de Melo >> AuthorDate: Thu Apr 19 20:43:29 2007 -0700 >> Committer: David S. Miller >> CommitDate: Wed Apr 25 22:26:29 2007 -0700 >> >> [SK_BUFF]: Convert skb->end to sk_buff_data_t >> >> Now to convert the last one, skb->data, that will allow many simplifications >> and removal of some of the offset helpers. >> >> Signed-off-by: Arnaldo Carvalho de Melo >> Signed-off-by: David S. Miller >> > > This patch and the previous one breaks the compilation on one of my > machines. Specifically, this bit: > > >> @@ -632,12 +644,13 @@ int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail, >> /* Copy only real data... and, alas, header. This should be >> * optimized for the cases when header is void. */ >> memcpy(data + nhead, skb->head, >> - skb->tail >> -#ifndef NET_SKBUFF_DATA_USES_OFFSET >> - - skb->head >> +#ifdef NET_SKBUFF_DATA_USES_OFFSET >> + skb->tail); >> +#else >> + skb->tail - skb->head); >> #endif >> - ); >> - memcpy(data + size, skb->end, sizeof(struct skb_shared_info)); >> + memcpy(data + size, skb_end_pointer(skb), >> + sizeof(struct skb_shared_info)); >> >> for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) >> get_page(skb_shinfo(skb)->frags[i].page); >> > > Causes this compile error: > > /home/muli/kernel/trident/trident.git/net/core/skbuff.c:648:1: directives may not be used inside a macro argument > /home/muli/kernel/trident/trident.git/net/core/skbuff.c:647:39: unterminated argument list invoking macro "memcpy" > /home/muli/kernel/trident/trident.git/net/core/skbuff.c: In function `pskb_expand_head': > /home/muli/kernel/trident/trident.git/net/core/skbuff.c:651: `memcpy' undeclared (first use in this function) > /home/muli/kernel/trident/trident.git/net/core/skbuff.c:651: (Each undeclared identifier is reported only once > /home/muli/kernel/trident/trident.git/net/core/skbuff.c:651: for each function it appears in.) > /home/muli/kernel/trident/trident.git/net/core/skbuff.c:651: syntax error before "skb" > > muli@rhun:~/kernel/trident/trident.git$ gcc -v > Reading specs from /usr/lib/gcc-lib/i386-redhat-linux/3.2.3/specs > Configured with: ../configure --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --enable-shared --enable-threads=posix --disable-checking --with-system-zlib --enable-__cxa_atexit --host=i386-redhat-linux > Thread model: posix > gcc version 3.2.3 20030502 (Red Hat Linux 3.2.3-53) > > It happens because memcpy ends up being a macro, and this gcc dislikes > having a preprocessor directive inside a macro argument. I don't know > if if it's valid in general, but Documentation/Changes does say we > still support gcc 3.2... > Well, the fix is easy, can you provide a patch? - Arnaldo