Re: [PATCH] debugfs: Check return value of debugfs_real_fops() for NULL

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Wed, Mar 28, 2018 at 11:14:56AM -0700, Matthias Kaehlcke wrote:
> El Wed, Mar 28, 2018 at 08:05:56PM +0200 Greg Kroah-Hartman ha dit:
> 
> > 
> > A: Because it messes up the order in which people normally read text.
> > Q: Why is top-posting such a bad thing?
> > A: Top-posting.
> > Q: What is the most annoying thing in e-mail?
> > 
> > A: No.
> > Q: Should I include quotations after my reply?
> > 
> > http://daringfireball.net/2007/07/on_top
> > 
> > On Wed, Mar 28, 2018 at 07:47:53AM -0700, Manoj Gupta wrote:
> > > Please note that there is nothing wrong in the generated code, just
> > > that it confuses objtool.
> > 
> > Then fix the tool, the C code is correct :)
> > 
> > > Clang has simply omitted the statement where NULL is returned since
> > > the pointer was always dereferenced post inlining.
> > 
> > Then tell clang not to do that, like we tell gcc not to do that as that
> > is a foolish thing for a compiler to do when building the kernel.
> 
> Thanks all for your input, we'll try to get
> -fno-delete-null-pointer-checks or a similar flag to be added to
> clang.

Wait, clang does not have that?  That's crazy, how has this not been hit
yet when building the kernel?

confused,

greg k-h