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From: David Miller on 26 Feb 2010 05:00 From: Dan Carpenter <error27(a)gmail.com> Date: Fri, 26 Feb 2010 12:49:41 +0300 > get_phy_device() can return an ERR_PTR() > > Signed-off-by: Dan Carpenter <error27(a)gmail.com> > --- > I don't have a cross compile environment set up so I can't even compile > test this. :/ But err.h is included so it should be OK. It should return ERR_PTR() consistently. Checking for both NULL and ERR_PTR() is undesirable. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Grant Likely on 26 Feb 2010 11:20
On Fri, Feb 26, 2010 at 2:54 AM, David Miller <davem(a)davemloft.net> wrote: > From: Dan Carpenter <error27(a)gmail.com> > Date: Fri, 26 Feb 2010 12:49:41 +0300 > >> get_phy_device() can return an ERR_PTR() >> >> Signed-off-by: Dan Carpenter <error27(a)gmail.com> >> --- >> I don't have a cross compile environment set up so I can't even compile >> test this. �:/ �But err.h is included so it should be OK. > > It should return ERR_PTR() consistently. �Checking for both > NULL and ERR_PTR() is undesirable. Ugh. This is why I dislike the ERR_PTR() pattern so much. The compiler cannot do any type checking and it is implemented inconsistently. You have to go look at the calling function to find out what you're allowed to do with the return value. ie. which test do I use? (!ptr) or IS_ERR(ptr)? It would be better if ERR_PTR() returned a structure or a union. At least that way the compiler would yell at you if the an ERR_PTR was being returned. g. -- Grant Likely, B.Sc., P.Eng. Secret Lab Technologies Ltd. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |