Re: [PATCH 2/2] arch/x86: Fix sparse warning symbol not declared

From: Tobin Harding
Date: Mon Feb 13 2017 - 15:27:12 EST

On Sun, Feb 12, 2017 at 12:06:47PM +0100, Thomas Gleixner wrote:
> On Sun, 12 Feb 2017, Tobin C. Harding wrote:
> > This patch adds function declaration in order to quiet sparse symbol
> > not declared warning.
> Same comment vs. 'This patch' as before. Hint, we already know that this is
> a patch, otherwise it would be mislabeled.
> >
> > Signed-off-by: Tobin C. Harding <me@xxxxxxxx>
> > ---
> >
> > Unsure why adding declaration quiets sparse.
> Because sparse finds a declaration before the definition.
> > This may not be the correct solution.
> Right, it's not.
> > Only testing done is building and booting kernel. Since 'purgatory' is
> > called from assembler and does not need forward declaration the only
> > advantage to this patch seems to be to save the next newbie from
> > investigating the sparse warning.
> Well, yes. But just quietening a checker by slapping a pointless forward
> declaration into the code is not pretty either. A smarter checker might
> catch that.
> The proper solution is to have a local include file 'purgatory.h' and put
> the declaration there. Include it in both files even if that's not required
> for the ASM file. But that documents, that the function is used outside of
> purgatory.c

Blindly following instructions led to the bone headed patch I
submitted yesterday (without building). Is there some way to include a
C header in an ASM file that I do not know about?

Thanks for patiently pointing out how to write a commit log. May I
please bother you with another small etiquette question. Should I
have replayed to you as I have done so or should I have re-sent another
patch (v3) with the mistakes fixed (and stated in the log that I did
not know how to implement the suggestions).