Re: [PATCH] mips/oprofile: Fix fallthrough placement

[Thomas Bogendoerfer]

On Fri, Aug 21, 2020 at 04:23:28AM -0500, Gustavo A. R. Silva wrote:
> 
> 
> On 8/21/20 03:46, He Zhe wrote:
> > 
> > 
> > On 8/21/20 3:48 PM, Thomas Bogendoerfer wrote:
> >> On Thu, Aug 20, 2020 at 08:54:40PM +0800, zhe.he@xxxxxxxxxxxxx wrote:
> >>> From: He Zhe <zhe.he@xxxxxxxxxxxxx>
> >>>
> >>> We want neither
> >>> "
> >>> include/linux/compiler_attributes.h:201:41: warning: statement will never
> >>> be executed [-Wswitch-unreachable]
> >>>   201 | # define fallthrough __attribute__((__fallthrough__))
> >>>       |                      ^~~~~~~~~~~~~
> >>> "
> >>> nor
> >>> "
> >>> include/linux/compiler_attributes.h:201:41: warning: attribute
> >>> 'fallthrough' not preceding a case label or default label
> >>>   201 | # define fallthrough __attribute__((__fallthrough__))
> >>>       |                      ^~~~~~~~~~~~~
> >>> "
> >>>
> >>> It's not worth adding one more macro. Let's simply place the fallthrough
> >>> in between the expansions.
> >>>
> >>> Signed-off-by: He Zhe <zhe.he@xxxxxxxxxxxxx>
> >> there is already another patch for the problem, which I've applied
> >> to mips-fixes.
> > 
> > You mean the below one?
> > https://git.kernel.org/pub/scm/linux/kernel/git/mips/linux.git/commit/?h=mips-fixes&id=5900acb374fe2f4f42bbcb2c84db64f582d917a1
> > 
> > That patch handles the first warning in my commit log but does not handle the
> > second one which is introduced since gcc v10.1.0 commit 6c80b1b56dec
> > ("Make more bad uses of fallthrough attribute into pedwarns.").
> > 
> 
> This is true.
> 
> Thomas, please apply this patch instead of mine. Also, consider adding
> the Fixes tag and CC stable due to the non-executable code error, and
> my Reviewed-by:
> 
> Fixes: c9b029903466 ("MIPS: Use fallthrough for arch/mips")
> Cc: stable@xxxxxxxxxxxxxxx
> Reviewed-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>

done.

Thomas.

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