From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Jesper Juhl" Subject: Re: [PATCH 13/30] net: Don't do pointless kmalloc return value casts in zd1211 driver Date: Thu, 30 Aug 2007 22:20:23 +0200 Message-ID: <9a8748490708301320o49d8e794vc5c37ffc938006f1@mail.gmail.com> References: <1554af80879a7ef2f78a4d654f23c248203500d9.1187912217.git.jesper.juhl@gmail.com> <46D70467.1040109@gentoo.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: "Linux Kernel Mailing List" , netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, "David S. Miller" , "Ulrich Kunitz" , linux-wireless-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: "Daniel Drake" Return-path: In-Reply-To: <46D70467.1040109-aBrp7R+bbdUdnm+yROfE0A@public.gmane.org> Content-Disposition: inline Sender: linux-wireless-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org On 30/08/2007, Daniel Drake wrote: > Jesper Juhl wrote: > > Since kmalloc() returns a void pointer there is no reason to cast > > its return value. > > This patch also removes a pointless initialization of a variable. > > NAK: adds a sparse warning > zd_chip.c:116:15: warning: implicit cast to nocast type > Ok, I must admit I didn't check with sparse since it seemed pointless - we usually never cast void pointers to other pointer types, specifically because the C language nicely guarantees that the right thing will happen without the cast. Sometimes we have to cast them to integer types, su sure we need the cast there. But what on earth makes a "zd_addr_t *" so special that we have to explicitly cast a "void *" to that type? I see it's defined as typedef u32 __nocast zd_addr_t; in drivers/net/wireless/zd1211rw/zd_types.h , but why the __nocast ? What would be wrong in applying my patch that removes the cast of the kmalloc() return value and then also remove the "__nocast" here? -- Jesper Juhl Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html Plain text mails only, please http://www.expita.com/nomime.html