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From: Nick Desaulniers <ndesaulniers@google.com>
Date: Mon, 19 Oct 2020 12:42:15 -0700
Message-ID: <CAKwvOdkR_Ttfo7_JKUiZFVqr=Uh=4b05KCPCSuzwk=zaWtA2_Q@mail.gmail.com>
Subject: Re: [RFC] treewide: cleanup unreachable breaks
To: Tom Rix <trix@redhat.com>
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On Sat, Oct 17, 2020 at 10:43 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Sat, Oct 17, 2020 at 09:09:28AM -0700, trix@redhat.com wrote:
> > From: Tom Rix <trix@redhat.com>
> >
> > This is a upcoming change to clean up a new warning treewide.
> > I am wondering if the change could be one mega patch (see below) or
> > normal patch per file about 100 patches or somewhere half way by collecting
> > early acks.
>
> Please break it up into one-patch-per-subsystem, like normal, and get it
> merged that way.
>
> Sending us a patch, without even a diffstat to review, isn't going to
> get you very far...

Tom,
If you're able to automate this cleanup, I suggest checking in a
script that can be run on a directory.  Then for each subsystem you
can say in your commit "I ran scripts/fix_whatever.py on this subdir."
 Then others can help you drive the tree wide cleanup.  Then we can
enable -Wunreachable-code-break either by default, or W=2 right now
might be a good idea.

Ah, George (gbiv@, cc'ed), did an analysis recently of
`-Wunreachable-code-loop-increment`, `-Wunreachable-code-break`, and
`-Wunreachable-code-return` for Android userspace.  From the review:
```
Spoilers: of these, it seems useful to turn on
-Wunreachable-code-loop-increment and -Wunreachable-code-return by
default for Android
...
While these conventions about always having break arguably became
obsolete when we enabled -Wfallthrough, my sample turned up zero
potential bugs caught by this warning, and we'd need to put a lot of
effort into getting a clean tree. So this warning doesn't seem to be
worth it.
```
Looks like there's an order of magnitude of `-Wunreachable-code-break`
than the other two.

We probably should add all 3 to W=2 builds (wrapped in cc-option).
I've filed https://github.com/ClangBuiltLinux/linux/issues/1180 to
follow up on.
-- 
Thanks,
~Nick Desaulniers
_______________________________________________
Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org
To unsubscribe send an email to linux-nvdimm-leave@lists.01.org

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References: <20201017160928.12698-1-trix@redhat.com> <20201018054332.GB593954@kroah.com>
In-Reply-To: <20201018054332.GB593954@kroah.com>
From:   Nick Desaulniers <ndesaulniers@google.com>
Date:   Mon, 19 Oct 2020 12:42:15 -0700
Message-ID: <CAKwvOdkR_Ttfo7_JKUiZFVqr=Uh=4b05KCPCSuzwk=zaWtA2_Q@mail.gmail.com>
Subject: Re: [RFC] treewide: cleanup unreachable breaks
To:     Tom Rix <trix@redhat.com>
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On Sat, Oct 17, 2020 at 10:43 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Sat, Oct 17, 2020 at 09:09:28AM -0700, trix@redhat.com wrote:
> > From: Tom Rix <trix@redhat.com>
> >
> > This is a upcoming change to clean up a new warning treewide.
> > I am wondering if the change could be one mega patch (see below) or
> > normal patch per file about 100 patches or somewhere half way by collecting
> > early acks.
>
> Please break it up into one-patch-per-subsystem, like normal, and get it
> merged that way.
>
> Sending us a patch, without even a diffstat to review, isn't going to
> get you very far...

Tom,
If you're able to automate this cleanup, I suggest checking in a
script that can be run on a directory.  Then for each subsystem you
can say in your commit "I ran scripts/fix_whatever.py on this subdir."
 Then others can help you drive the tree wide cleanup.  Then we can
enable -Wunreachable-code-break either by default, or W=2 right now
might be a good idea.

Ah, George (gbiv@, cc'ed), did an analysis recently of
`-Wunreachable-code-loop-increment`, `-Wunreachable-code-break`, and
`-Wunreachable-code-return` for Android userspace.  From the review:
```
Spoilers: of these, it seems useful to turn on
-Wunreachable-code-loop-increment and -Wunreachable-code-return by
default for Android
...
While these conventions about always having break arguably became
obsolete when we enabled -Wfallthrough, my sample turned up zero
potential bugs caught by this warning, and we'd need to put a lot of
effort into getting a clean tree. So this warning doesn't seem to be
worth it.
```
Looks like there's an order of magnitude of `-Wunreachable-code-break`
than the other two.

We probably should add all 3 to W=2 builds (wrapped in cc-option).
I've filed https://github.com/ClangBuiltLinux/linux/issues/1180 to
follow up on.
-- 
Thanks,
~Nick Desaulniers

From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nick Desaulniers <ndesaulniers@google.com>
Date: Mon, 19 Oct 2020 19:42:15 +0000
Subject: Re: [RFC] treewide: cleanup unreachable breaks
Message-Id: <CAKwvOdkR_Ttfo7_JKUiZFVqr=Uh=4b05KCPCSuzwk=zaWtA2_Q@mail.gmail.com>
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References: <20201017160928.12698-1-trix@redhat.com>
 <20201018054332.GB593954@kroah.com>
In-Reply-To: <20201018054332.GB593954@kroah.com>
To: Tom Rix <trix@redhat.com>
Cc: alsa-devel@alsa-project.org, clang-built-linux <clang-built-linux@googlegroups.com>, Greg KH <gregkh@linuxfoundation.org>, linux-iio@vger.kernel.org, nouveau@lists.freedesktop.org, storagedev@microchip.com, dri-devel <dri-devel@lists.freedesktop.org>, virtualization@lists.linux-foundation.org, keyrings@vger.kernel.org, linux-mtd@lists.infradead.org, ath10k@lists.infradead.org, linux-stm32@st-md-mailman.stormreply.com, usb-storage@lists.one-eyed-alien.net, linux-watchdog@vger.kernel.org, devel@driverdev.osuosl.org, linux-samsung-soc@vger.kernel.org, linux-scsi@vger.kernel.org, linux-nvdimm <linux-nvdimm@lists.01.org>, amd-gfx list <amd-gfx@lists.freedesktop.org>, linux-acpi@vger.kernel.org, intel-wired-lan@lists.osuosl.org, industrypack-devel@lists.sourceforge.net, linux-pci@vger.kernel.org, spice-devel@lists.freedesktop.org, MPT-FusionLinux.pdl@broadcom.com, linux-media@vger.kernel.org, linux-serial@vger.kernel.org, linux-nfc@lists.01.org, linux-pm@vger.kernel.org, linux-can@vger.kernel.org, linux-block@vger.kernel.org, linux-gpio@vger.kernel.org, xen-devel@lists.xenproject.org, linux-amlogic@lists.infradead.org, openipmi-developer@lists.sourceforge.net, platform-driver-x86@vger.kernel.org, linux-integrity@vger.kernel.org, Linux ARM <linux-arm-kernel@lists.infradead.org>, linux-edac@vger.kernel.org, George Burgess <gbiv@google.com>, Network Development <netdev@vger.kernel.org>, linux-usb@vger.kernel.org, linux-wireless <linux-wireless@vger.kernel.org>, LKML <linux-kernel@vger.kernel.org>, linux-security-module@vger.kernel.org, "open list:HARDWARE RANDOM NUMBER GENERATOR CORE" <linux-crypto@vger.kernel.org>, patches@opensource.cirrus.com, bpf <bpf@vger.kernel.org>, ocfs2-devel@oss.oracle.com, linux-power@fi.rohmeurope.com

On Sat, Oct 17, 2020 at 10:43 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Sat, Oct 17, 2020 at 09:09:28AM -0700, trix@redhat.com wrote:
> > From: Tom Rix <trix@redhat.com>
> >
> > This is a upcoming change to clean up a new warning treewide.
> > I am wondering if the change could be one mega patch (see below) or
> > normal patch per file about 100 patches or somewhere half way by collecting
> > early acks.
>
> Please break it up into one-patch-per-subsystem, like normal, and get it
> merged that way.
>
> Sending us a patch, without even a diffstat to review, isn't going to
> get you very far...

Tom,
If you're able to automate this cleanup, I suggest checking in a
script that can be run on a directory.  Then for each subsystem you
can say in your commit "I ran scripts/fix_whatever.py on this subdir."
 Then others can help you drive the tree wide cleanup.  Then we can
enable -Wunreachable-code-break either by default, or W=2 right now
might be a good idea.

Ah, George (gbiv@, cc'ed), did an analysis recently of
`-Wunreachable-code-loop-increment`, `-Wunreachable-code-break`, and
`-Wunreachable-code-return` for Android userspace.  From the review:
```
Spoilers: of these, it seems useful to turn on
-Wunreachable-code-loop-increment and -Wunreachable-code-return by
default for Android
...
While these conventions about always having break arguably became
obsolete when we enabled -Wfallthrough, my sample turned up zero
potential bugs caught by this warning, and we'd need to put a lot of
effort into getting a clean tree. So this warning doesn't seem to be
worth it.
```
Looks like there's an order of magnitude of `-Wunreachable-code-break`
than the other two.

We probably should add all 3 to W=2 builds (wrapped in cc-option).
I've filed https://github.com/ClangBuiltLinux/linux/issues/1180 to
follow up on.
-- 
Thanks,
~Nick Desaulniers

From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nick Desaulniers <ndesaulniers@google.com>
Date: Mon, 19 Oct 2020 12:42:15 -0700
Subject: [Ocfs2-devel] [RFC] treewide: cleanup unreachable breaks
In-Reply-To: <20201018054332.GB593954@kroah.com>
References: <20201017160928.12698-1-trix@redhat.com>
	<20201018054332.GB593954@kroah.com>
Message-ID: <CAKwvOdkR_Ttfo7_JKUiZFVqr=Uh=4b05KCPCSuzwk=zaWtA2_Q@mail.gmail.com>
List-Id: <ocfs2-devel.oss.oracle.com>
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To: Tom Rix <trix@redhat.com>
Cc: alsa-devel@alsa-project.org, clang-built-linux <clang-built-linux@googlegroups.com>, Greg KH <gregkh@linuxfoundation.org>, linux-iio@vger.kernel.org, nouveau@lists.freedesktop.org, storagedev@microchip.com, dri-devel <dri-devel@lists.freedesktop.org>, virtualization@lists.linux-foundation.org, keyrings@vger.kernel.org, linux-mtd@lists.infradead.org, ath10k@lists.infradead.org, linux-stm32@st-md-mailman.stormreply.com, usb-storage@lists.one-eyed-alien.net, linux-watchdog@vger.kernel.org, devel@driverdev.osuosl.org, linux-samsung-soc@vger.kernel.org, linux-scsi@vger.kernel.org, linux-nvdimm <linux-nvdimm@lists.01.org>, amd-gfx list <amd-gfx@lists.freedesktop.org>, linux-acpi@vger.kernel.org, intel-wired-lan@lists.osuosl.org, industrypack-devel@lists.sourceforge.net, linux-pci@vger.kernel.org, spice-devel@lists.freedesktop.org, MPT-FusionLinux.pdl@broadcom.com, linux-media@vger.kernel.org, linux-serial@vger.kernel.org, linux-nfc@lists.01.org, linux-pm@vger.kernel.org, linux-can@vger.kernel.org, linux-block@vger.kernel.org, linux-gpio@vger.kernel.org, xen-devel@lists.xenproject.org, linux-amlogic@lists.infradead.org, openipmi-developer@lists.sourceforge.net, platform-driver-x86@vger.kernel.org, linux-integrity@vger.kernel.org, Linux ARM <linux-arm-kernel@lists.infradead.org>, linux-edac@vger.kernel.org, George Burgess <gbiv@google.com>, Network Development <netdev@vger.kernel.org>, linux-usb@vger.kernel.org, linux-wireless <linux-wireless@vger.kernel.org>, LKML <linux-kernel@vger.kernel.org>, linux-security-module@vger.kernel.org, "open list:HARDWARE RANDOM NUMBER GENERATOR CORE" <linux-crypto@vger.kernel.org>, patches@opensource.cirrus.com, bpf <bpf@vger.kernel.org>, ocfs2-devel@oss.oracle.com, linux-power@fi.rohmeurope.com

On Sat, Oct 17, 2020 at 10:43 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Sat, Oct 17, 2020 at 09:09:28AM -0700, trix at redhat.com wrote:
> > From: Tom Rix <trix@redhat.com>
> >
> > This is a upcoming change to clean up a new warning treewide.
> > I am wondering if the change could be one mega patch (see below) or
> > normal patch per file about 100 patches or somewhere half way by collecting
> > early acks.
>
> Please break it up into one-patch-per-subsystem, like normal, and get it
> merged that way.
>
> Sending us a patch, without even a diffstat to review, isn't going to
> get you very far...

Tom,
If you're able to automate this cleanup, I suggest checking in a
script that can be run on a directory.  Then for each subsystem you
can say in your commit "I ran scripts/fix_whatever.py on this subdir."
 Then others can help you drive the tree wide cleanup.  Then we can
enable -Wunreachable-code-break either by default, or W=2 right now
might be a good idea.

Ah, George (gbiv@, cc'ed), did an analysis recently of
`-Wunreachable-code-loop-increment`, `-Wunreachable-code-break`, and
`-Wunreachable-code-return` for Android userspace.  From the review:
```
Spoilers: of these, it seems useful to turn on
-Wunreachable-code-loop-increment and -Wunreachable-code-return by
default for Android
...
While these conventions about always having break arguably became
obsolete when we enabled -Wfallthrough, my sample turned up zero
potential bugs caught by this warning, and we'd need to put a lot of
effort into getting a clean tree. So this warning doesn't seem to be
worth it.
```
Looks like there's an order of magnitude of `-Wunreachable-code-break`
than the other two.

We probably should add all 3 to W=2 builds (wrapped in cc-option).
I've filed https://github.com/ClangBuiltLinux/linux/issues/1180 to
follow up on.
-- 
Thanks,
~Nick Desaulniers

From mboxrd@z Thu Jan  1 00:00:00 1970
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From: Nick Desaulniers <ndesaulniers@google.com>
Date: Mon, 19 Oct 2020 12:42:15 -0700
Message-ID: <CAKwvOdkR_Ttfo7_JKUiZFVqr=Uh=4b05KCPCSuzwk=zaWtA2_Q@mail.gmail.com>
Subject: Re: [RFC] treewide: cleanup unreachable breaks
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On Sat, Oct 17, 2020 at 10:43 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Sat, Oct 17, 2020 at 09:09:28AM -0700, trix@redhat.com wrote:
> > From: Tom Rix <trix@redhat.com>
> >
> > This is a upcoming change to clean up a new warning treewide.
> > I am wondering if the change could be one mega patch (see below) or
> > normal patch per file about 100 patches or somewhere half way by collecting
> > early acks.
>
> Please break it up into one-patch-per-subsystem, like normal, and get it
> merged that way.
>
> Sending us a patch, without even a diffstat to review, isn't going to
> get you very far...

Tom,
If you're able to automate this cleanup, I suggest checking in a
script that can be run on a directory.  Then for each subsystem you
can say in your commit "I ran scripts/fix_whatever.py on this subdir."
 Then others can help you drive the tree wide cleanup.  Then we can
enable -Wunreachable-code-break either by default, or W=2 right now
might be a good idea.

Ah, George (gbiv@, cc'ed), did an analysis recently of
`-Wunreachable-code-loop-increment`, `-Wunreachable-code-break`, and
`-Wunreachable-code-return` for Android userspace.  From the review:
```
Spoilers: of these, it seems useful to turn on
-Wunreachable-code-loop-increment and -Wunreachable-code-return by
default for Android
...
While these conventions about always having break arguably became
obsolete when we enabled -Wfallthrough, my sample turned up zero
potential bugs caught by this warning, and we'd need to put a lot of
effort into getting a clean tree. So this warning doesn't seem to be
worth it.
```
Looks like there's an order of magnitude of `-Wunreachable-code-break`
than the other two.

We probably should add all 3 to W=2 builds (wrapped in cc-option).
I've filed https://github.com/ClangBuiltLinux/linux/issues/1180 to
follow up on.
-- 
Thanks,
~Nick Desaulniers
_______________________________________________
devel mailing list
devel@linuxdriverproject.org
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel

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From: Nick Desaulniers <ndesaulniers@google.com>
Date: Mon, 19 Oct 2020 12:42:15 -0700
Message-ID: <CAKwvOdkR_Ttfo7_JKUiZFVqr=Uh=4b05KCPCSuzwk=zaWtA2_Q@mail.gmail.com>
Subject: Re: [RFC] treewide: cleanup unreachable breaks
To: Tom Rix <trix@redhat.com>
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Cc: alsa-devel@alsa-project.org,
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 Greg KH <gregkh@linuxfoundation.org>, linux-iio@vger.kernel.org,
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On Sat, Oct 17, 2020 at 10:43 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Sat, Oct 17, 2020 at 09:09:28AM -0700, trix@redhat.com wrote:
> > From: Tom Rix <trix@redhat.com>
> >
> > This is a upcoming change to clean up a new warning treewide.
> > I am wondering if the change could be one mega patch (see below) or
> > normal patch per file about 100 patches or somewhere half way by collecting
> > early acks.
>
> Please break it up into one-patch-per-subsystem, like normal, and get it
> merged that way.
>
> Sending us a patch, without even a diffstat to review, isn't going to
> get you very far...

Tom,
If you're able to automate this cleanup, I suggest checking in a
script that can be run on a directory.  Then for each subsystem you
can say in your commit "I ran scripts/fix_whatever.py on this subdir."
 Then others can help you drive the tree wide cleanup.  Then we can
enable -Wunreachable-code-break either by default, or W=2 right now
might be a good idea.

Ah, George (gbiv@, cc'ed), did an analysis recently of
`-Wunreachable-code-loop-increment`, `-Wunreachable-code-break`, and
`-Wunreachable-code-return` for Android userspace.  From the review:
```
Spoilers: of these, it seems useful to turn on
-Wunreachable-code-loop-increment and -Wunreachable-code-return by
default for Android
...
While these conventions about always having break arguably became
obsolete when we enabled -Wfallthrough, my sample turned up zero
potential bugs caught by this warning, and we'd need to put a lot of
effort into getting a clean tree. So this warning doesn't seem to be
worth it.
```
Looks like there's an order of magnitude of `-Wunreachable-code-break`
than the other two.

We probably should add all 3 to W=2 builds (wrapped in cc-option).
I've filed https://github.com/ClangBuiltLinux/linux/issues/1180 to
follow up on.
-- 
Thanks,
~Nick Desaulniers

From mboxrd@z Thu Jan  1 00:00:00 1970
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 <20201018054332.GB593954@kroah.com>
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From: Nick Desaulniers <ndesaulniers@google.com>
Date: Mon, 19 Oct 2020 12:42:15 -0700
Message-ID: <CAKwvOdkR_Ttfo7_JKUiZFVqr=Uh=4b05KCPCSuzwk=zaWtA2_Q@mail.gmail.com>
Subject: Re: [RFC] treewide: cleanup unreachable breaks
To: Tom Rix <trix@redhat.com>
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On Sat, Oct 17, 2020 at 10:43 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Sat, Oct 17, 2020 at 09:09:28AM -0700, trix@redhat.com wrote:
> > From: Tom Rix <trix@redhat.com>
> >
> > This is a upcoming change to clean up a new warning treewide.
> > I am wondering if the change could be one mega patch (see below) or
> > normal patch per file about 100 patches or somewhere half way by collecting
> > early acks.
>
> Please break it up into one-patch-per-subsystem, like normal, and get it
> merged that way.
>
> Sending us a patch, without even a diffstat to review, isn't going to
> get you very far...

Tom,
If you're able to automate this cleanup, I suggest checking in a
script that can be run on a directory.  Then for each subsystem you
can say in your commit "I ran scripts/fix_whatever.py on this subdir."
 Then others can help you drive the tree wide cleanup.  Then we can
enable -Wunreachable-code-break either by default, or W=2 right now
might be a good idea.

Ah, George (gbiv@, cc'ed), did an analysis recently of
`-Wunreachable-code-loop-increment`, `-Wunreachable-code-break`, and
`-Wunreachable-code-return` for Android userspace.  From the review:
```
Spoilers: of these, it seems useful to turn on
-Wunreachable-code-loop-increment and -Wunreachable-code-return by
default for Android
...
While these conventions about always having break arguably became
obsolete when we enabled -Wfallthrough, my sample turned up zero
potential bugs caught by this warning, and we'd need to put a lot of
effort into getting a clean tree. So this warning doesn't seem to be
worth it.
```
Looks like there's an order of magnitude of `-Wunreachable-code-break`
than the other two.

We probably should add all 3 to W=2 builds (wrapped in cc-option).
I've filed https://github.com/ClangBuiltLinux/linux/issues/1180 to
follow up on.
-- 
Thanks,
~Nick Desaulniers

______________________________________________________
Linux MTD discussion mailing list
http://lists.infradead.org/mailman/listinfo/linux-mtd/

From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nick Desaulniers <ndesaulniers@google.com>
Subject: Re: [RFC] treewide: cleanup unreachable breaks
Date: Mon, 19 Oct 2020 12:42:15 -0700
Message-ID: <CAKwvOdkR_Ttfo7_JKUiZFVqr=Uh=4b05KCPCSuzwk=zaWtA2_Q@mail.gmail.com>
References: <20201017160928.12698-1-trix@redhat.com> <20201018054332.GB593954@kroah.com>
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In-Reply-To: <20201018054332.GB593954@kroah.com>
To: Tom Rix <trix@redhat.com>
Cc: LKML <linux-kernel@vger.kernel.org>, linux-edac@vger.kernel.org, linux-acpi@vger.kernel.org, linux-pm@vger.kernel.org, xen-devel@lists.xenproject.org, linux-block@vger.kernel.org, openipmi-developer@lists.sourceforge.net, "open list:HARDWARE RANDOM NUMBER GENERATOR CORE" <linux-crypto@vger.kernel.org>, Linux ARM <linux-arm-kernel@lists.infradead.org>, linux-power@fi.rohmeurope.com, linux-gpio@vger.kernel.org, amd-gfx list <amd-gfx@lists.freedesktop.org>, dri-devel <dri-devel@lists.freedesktop.org>, nouveau@lists.freedesktop.org, virtualization@lists.linux-foundation.org, spice-devel@lists.freedesktop.org, linux-iio@vger.kernel.org, linux-amlogic@lists.infradead.org, industrypack-devel@lists.sourceforge.net, linux-media@vger.kernel.org, MPT-FusionLinux.pdl@broadcom.
List-Id: nouveau.vger.kernel.org

On Sat, Oct 17, 2020 at 10:43 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Sat, Oct 17, 2020 at 09:09:28AM -0700, trix@redhat.com wrote:
> > From: Tom Rix <trix@redhat.com>
> >
> > This is a upcoming change to clean up a new warning treewide.
> > I am wondering if the change could be one mega patch (see below) or
> > normal patch per file about 100 patches or somewhere half way by collecting
> > early acks.
>
> Please break it up into one-patch-per-subsystem, like normal, and get it
> merged that way.
>
> Sending us a patch, without even a diffstat to review, isn't going to
> get you very far...

Tom,
If you're able to automate this cleanup, I suggest checking in a
script that can be run on a directory.  Then for each subsystem you
can say in your commit "I ran scripts/fix_whatever.py on this subdir."
 Then others can help you drive the tree wide cleanup.  Then we can
enable -Wunreachable-code-break either by default, or W=2 right now
might be a good idea.

Ah, George (gbiv@, cc'ed), did an analysis recently of
`-Wunreachable-code-loop-increment`, `-Wunreachable-code-break`, and
`-Wunreachable-code-return` for Android userspace.  From the review:
```
Spoilers: of these, it seems useful to turn on
-Wunreachable-code-loop-increment and -Wunreachable-code-return by
default for Android
...
While these conventions about always having break arguably became
obsolete when we enabled -Wfallthrough, my sample turned up zero
potential bugs caught by this warning, and we'd need to put a lot of
effort into getting a clean tree. So this warning doesn't seem to be
worth it.
```
Looks like there's an order of magnitude of `-Wunreachable-code-break`
than the other two.

We probably should add all 3 to W=2 builds (wrapped in cc-option).
I've filed https://github.com/ClangBuiltLinux/linux/issues/1180 to
follow up on.
-- 
Thanks,
~Nick Desaulniers

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References: <20201017160928.12698-1-trix@redhat.com>
 <20201018054332.GB593954@kroah.com>
In-Reply-To: <20201018054332.GB593954@kroah.com>
Date: Mon, 19 Oct 2020 12:42:15 -0700
Message-ID: <CAKwvOdkR_Ttfo7_JKUiZFVqr=Uh=4b05KCPCSuzwk=zaWtA2_Q@mail.gmail.com>
Subject: Re: [RFC] treewide: cleanup unreachable breaks
To: Tom Rix <trix@redhat.com>
Cc: alsa-devel@alsa-project.org,
 clang-built-linux <clang-built-linux@googlegroups.com>,
 Greg KH <gregkh@linuxfoundation.org>, linux-iio@vger.kernel.org,
 nouveau@lists.freedesktop.org, storagedev@microchip.com,
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From: Nick Desaulniers via Virtualization
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On Sat, Oct 17, 2020 at 10:43 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Sat, Oct 17, 2020 at 09:09:28AM -0700, trix@redhat.com wrote:
> > From: Tom Rix <trix@redhat.com>
> >
> > This is a upcoming change to clean up a new warning treewide.
> > I am wondering if the change could be one mega patch (see below) or
> > normal patch per file about 100 patches or somewhere half way by collecting
> > early acks.
>
> Please break it up into one-patch-per-subsystem, like normal, and get it
> merged that way.
>
> Sending us a patch, without even a diffstat to review, isn't going to
> get you very far...

Tom,
If you're able to automate this cleanup, I suggest checking in a
script that can be run on a directory.  Then for each subsystem you
can say in your commit "I ran scripts/fix_whatever.py on this subdir."
 Then others can help you drive the tree wide cleanup.  Then we can
enable -Wunreachable-code-break either by default, or W=2 right now
might be a good idea.

Ah, George (gbiv@, cc'ed), did an analysis recently of
`-Wunreachable-code-loop-increment`, `-Wunreachable-code-break`, and
`-Wunreachable-code-return` for Android userspace.  From the review:
```
Spoilers: of these, it seems useful to turn on
-Wunreachable-code-loop-increment and -Wunreachable-code-return by
default for Android
...
While these conventions about always having break arguably became
obsolete when we enabled -Wfallthrough, my sample turned up zero
potential bugs caught by this warning, and we'd need to put a lot of
effort into getting a clean tree. So this warning doesn't seem to be
worth it.
```
Looks like there's an order of magnitude of `-Wunreachable-code-break`
than the other two.

We probably should add all 3 to W=2 builds (wrapped in cc-option).
I've filed https://github.com/ClangBuiltLinux/linux/issues/1180 to
follow up on.
-- 
Thanks,
~Nick Desaulniers
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization

From mboxrd@z Thu Jan  1 00:00:00 1970
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 <20201018054332.GB593954@kroah.com>
In-Reply-To: <20201018054332.GB593954@kroah.com>
From: Nick Desaulniers <ndesaulniers@google.com>
Date: Mon, 19 Oct 2020 12:42:15 -0700
Message-ID: <CAKwvOdkR_Ttfo7_JKUiZFVqr=Uh=4b05KCPCSuzwk=zaWtA2_Q@mail.gmail.com>
Subject: Re: [RFC] treewide: cleanup unreachable breaks
To: Tom Rix <trix@redhat.com>
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Cc: alsa-devel@alsa-project.org,
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 Linux ARM <linux-arm-kernel@lists.infradead.org>, linux-edac@vger.kernel.org,
 George Burgess <gbiv@google.com>, Network Development <netdev@vger.kernel.org>,
 linux-usb@vger.kernel.org, linux-wireless <linux-wireless@vger.kernel.org>,
 LKML <linux-kernel@vger.kernel.org>, linux-security-module@vger.kernel.org,
 "open list:HARDWARE RANDOM NUMBER GENERATOR CORE"
 <linux-crypto@vger.kernel.org>, patches@opensource.cirrus.com,
 bpf <bpf@vger.kernel.org>, ocfs2-devel@oss.oracle.com,
 linux-power@fi.rohmeurope.com
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Errors-To: dri-devel-bounces@lists.freedesktop.org
Sender: "dri-devel" <dri-devel-bounces@lists.freedesktop.org>

On Sat, Oct 17, 2020 at 10:43 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Sat, Oct 17, 2020 at 09:09:28AM -0700, trix@redhat.com wrote:
> > From: Tom Rix <trix@redhat.com>
> >
> > This is a upcoming change to clean up a new warning treewide.
> > I am wondering if the change could be one mega patch (see below) or
> > normal patch per file about 100 patches or somewhere half way by collecting
> > early acks.
>
> Please break it up into one-patch-per-subsystem, like normal, and get it
> merged that way.
>
> Sending us a patch, without even a diffstat to review, isn't going to
> get you very far...

Tom,
If you're able to automate this cleanup, I suggest checking in a
script that can be run on a directory.  Then for each subsystem you
can say in your commit "I ran scripts/fix_whatever.py on this subdir."
 Then others can help you drive the tree wide cleanup.  Then we can
enable -Wunreachable-code-break either by default, or W=2 right now
might be a good idea.

Ah, George (gbiv@, cc'ed), did an analysis recently of
`-Wunreachable-code-loop-increment`, `-Wunreachable-code-break`, and
`-Wunreachable-code-return` for Android userspace.  From the review:
```
Spoilers: of these, it seems useful to turn on
-Wunreachable-code-loop-increment and -Wunreachable-code-return by
default for Android
...
While these conventions about always having break arguably became
obsolete when we enabled -Wfallthrough, my sample turned up zero
potential bugs caught by this warning, and we'd need to put a lot of
effort into getting a clean tree. So this warning doesn't seem to be
worth it.
```
Looks like there's an order of magnitude of `-Wunreachable-code-break`
than the other two.

We probably should add all 3 to W=2 builds (wrapped in cc-option).
I've filed https://github.com/ClangBuiltLinux/linux/issues/1180 to
follow up on.
-- 
Thanks,
~Nick Desaulniers
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

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 <20201018054332.GB593954@kroah.com>
In-Reply-To: <20201018054332.GB593954@kroah.com>
From: Nick Desaulniers <ndesaulniers@google.com>
Date: Mon, 19 Oct 2020 12:42:15 -0700
Message-ID: <CAKwvOdkR_Ttfo7_JKUiZFVqr=Uh=4b05KCPCSuzwk=zaWtA2_Q@mail.gmail.com>
Subject: Re: [RFC] treewide: cleanup unreachable breaks
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On Sat, Oct 17, 2020 at 10:43 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Sat, Oct 17, 2020 at 09:09:28AM -0700, trix@redhat.com wrote:
> > From: Tom Rix <trix@redhat.com>
> >
> > This is a upcoming change to clean up a new warning treewide.
> > I am wondering if the change could be one mega patch (see below) or
> > normal patch per file about 100 patches or somewhere half way by collecting
> > early acks.
>
> Please break it up into one-patch-per-subsystem, like normal, and get it
> merged that way.
>
> Sending us a patch, without even a diffstat to review, isn't going to
> get you very far...

Tom,
If you're able to automate this cleanup, I suggest checking in a
script that can be run on a directory.  Then for each subsystem you
can say in your commit "I ran scripts/fix_whatever.py on this subdir."
 Then others can help you drive the tree wide cleanup.  Then we can
enable -Wunreachable-code-break either by default, or W=2 right now
might be a good idea.

Ah, George (gbiv@, cc'ed), did an analysis recently of
`-Wunreachable-code-loop-increment`, `-Wunreachable-code-break`, and
`-Wunreachable-code-return` for Android userspace.  From the review:
```
Spoilers: of these, it seems useful to turn on
-Wunreachable-code-loop-increment and -Wunreachable-code-return by
default for Android
...
While these conventions about always having break arguably became
obsolete when we enabled -Wfallthrough, my sample turned up zero
potential bugs caught by this warning, and we'd need to put a lot of
effort into getting a clean tree. So this warning doesn't seem to be
worth it.
```
Looks like there's an order of magnitude of `-Wunreachable-code-break`
than the other two.

We probably should add all 3 to W=2 builds (wrapped in cc-option).
I've filed https://github.com/ClangBuiltLinux/linux/issues/1180 to
follow up on.
-- 
Thanks,
~Nick Desaulniers

_______________________________________________
ath10k mailing list
ath10k@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/ath10k

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From: Nick Desaulniers <ndesaulniers@google.com>
Date: Mon, 19 Oct 2020 12:42:15 -0700
Message-ID: <CAKwvOdkR_Ttfo7_JKUiZFVqr=Uh=4b05KCPCSuzwk=zaWtA2_Q@mail.gmail.com>
Subject: Re: [RFC] treewide: cleanup unreachable breaks
To: Tom Rix <trix@redhat.com>
Cc: LKML <linux-kernel@vger.kernel.org>, linux-edac@vger.kernel.org, 
	linux-acpi@vger.kernel.org, linux-pm@vger.kernel.org, 
	xen-devel@lists.xenproject.org, linux-block@vger.kernel.org, 
	openipmi-developer@lists.sourceforge.net, 
	"open list:HARDWARE RANDOM NUMBER GENERATOR CORE" <linux-crypto@vger.kernel.org>, 
	Linux ARM <linux-arm-kernel@lists.infradead.org>, linux-power@fi.rohmeurope.com, 
	linux-gpio@vger.kernel.org, amd-gfx list <amd-gfx@lists.freedesktop.org>, 
	dri-devel <dri-devel@lists.freedesktop.org>, nouveau@lists.freedesktop.org, 
	virtualization@lists.linux-foundation.org, spice-devel@lists.freedesktop.org, 
	linux-iio@vger.kernel.org, linux-amlogic@lists.infradead.org, 
	industrypack-devel@lists.sourceforge.net, linux-media@vger.kernel.org, 
	MPT-FusionLinux.pdl@broadcom.com, linux-scsi@vger.kernel.org, 
	linux-mtd@lists.infradead.org, linux-can@vger.kernel.org, 
	Network Development <netdev@vger.kernel.org>, intel-wired-lan@lists.osuosl.org, 
	ath10k@lists.infradead.org, linux-wireless <linux-wireless@vger.kernel.org>, 
	linux-stm32@st-md-mailman.stormreply.com, linux-nfc@lists.01.org, 
	linux-nvdimm <linux-nvdimm@lists.01.org>, linux-pci@vger.kernel.org, 
	linux-samsung-soc@vger.kernel.org, platform-driver-x86@vger.kernel.org, 
	patches@opensource.cirrus.com, storagedev@microchip.com, 
	devel@driverdev.osuosl.org, linux-serial@vger.kernel.org, 
	linux-usb@vger.kernel.org, usb-storage@lists.one-eyed-alien.net, 
	linux-watchdog@vger.kernel.org, ocfs2-devel@oss.oracle.com, 
	bpf <bpf@vger.kernel.org>, linux-integrity@vger.kernel.org, 
	linux-security-module@vger.kernel.org, keyrings@vger.kernel.org, 
	alsa-devel@alsa-project.org, 
	clang-built-linux <clang-built-linux@googlegroups.com>, Greg KH <gregkh@linuxfoundation.org>, 
	George Burgess <gbiv@google.com>
Content-Type: text/plain; charset="UTF-8"

On Sat, Oct 17, 2020 at 10:43 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Sat, Oct 17, 2020 at 09:09:28AM -0700, trix@redhat.com wrote:
> > From: Tom Rix <trix@redhat.com>
> >
> > This is a upcoming change to clean up a new warning treewide.
> > I am wondering if the change could be one mega patch (see below) or
> > normal patch per file about 100 patches or somewhere half way by collecting
> > early acks.
>
> Please break it up into one-patch-per-subsystem, like normal, and get it
> merged that way.
>
> Sending us a patch, without even a diffstat to review, isn't going to
> get you very far...

Tom,
If you're able to automate this cleanup, I suggest checking in a
script that can be run on a directory.  Then for each subsystem you
can say in your commit "I ran scripts/fix_whatever.py on this subdir."
 Then others can help you drive the tree wide cleanup.  Then we can
enable -Wunreachable-code-break either by default, or W=2 right now
might be a good idea.

Ah, George (gbiv@, cc'ed), did an analysis recently of
`-Wunreachable-code-loop-increment`, `-Wunreachable-code-break`, and
`-Wunreachable-code-return` for Android userspace.  From the review:
```
Spoilers: of these, it seems useful to turn on
-Wunreachable-code-loop-increment and -Wunreachable-code-return by
default for Android
...
While these conventions about always having break arguably became
obsolete when we enabled -Wfallthrough, my sample turned up zero
potential bugs caught by this warning, and we'd need to put a lot of
effort into getting a clean tree. So this warning doesn't seem to be
worth it.
```
Looks like there's an order of magnitude of `-Wunreachable-code-break`
than the other two.

We probably should add all 3 to W=2 builds (wrapped in cc-option).
I've filed https://github.com/ClangBuiltLinux/linux/issues/1180 to
follow up on.
-- 
Thanks,
~Nick Desaulniers


From mboxrd@z Thu Jan  1 00:00:00 1970
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 <20201018054332.GB593954@kroah.com>
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From: Nick Desaulniers <ndesaulniers@google.com>
Date: Mon, 19 Oct 2020 12:42:15 -0700
Message-ID: <CAKwvOdkR_Ttfo7_JKUiZFVqr=Uh=4b05KCPCSuzwk=zaWtA2_Q@mail.gmail.com>
Subject: Re: [RFC] treewide: cleanup unreachable breaks
To: Tom Rix <trix@redhat.com>
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On Sat, Oct 17, 2020 at 10:43 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Sat, Oct 17, 2020 at 09:09:28AM -0700, trix@redhat.com wrote:
> > From: Tom Rix <trix@redhat.com>
> >
> > This is a upcoming change to clean up a new warning treewide.
> > I am wondering if the change could be one mega patch (see below) or
> > normal patch per file about 100 patches or somewhere half way by collecting
> > early acks.
>
> Please break it up into one-patch-per-subsystem, like normal, and get it
> merged that way.
>
> Sending us a patch, without even a diffstat to review, isn't going to
> get you very far...

Tom,
If you're able to automate this cleanup, I suggest checking in a
script that can be run on a directory.  Then for each subsystem you
can say in your commit "I ran scripts/fix_whatever.py on this subdir."
 Then others can help you drive the tree wide cleanup.  Then we can
enable -Wunreachable-code-break either by default, or W=2 right now
might be a good idea.

Ah, George (gbiv@, cc'ed), did an analysis recently of
`-Wunreachable-code-loop-increment`, `-Wunreachable-code-break`, and
`-Wunreachable-code-return` for Android userspace.  From the review:
```
Spoilers: of these, it seems useful to turn on
-Wunreachable-code-loop-increment and -Wunreachable-code-return by
default for Android
...
While these conventions about always having break arguably became
obsolete when we enabled -Wfallthrough, my sample turned up zero
potential bugs caught by this warning, and we'd need to put a lot of
effort into getting a clean tree. So this warning doesn't seem to be
worth it.
```
Looks like there's an order of magnitude of `-Wunreachable-code-break`
than the other two.

We probably should add all 3 to W=2 builds (wrapped in cc-option).
I've filed https://github.com/ClangBuiltLinux/linux/issues/1180 to
follow up on.
-- 
Thanks,
~Nick Desaulniers
_______________________________________________
amd-gfx mailing list
amd-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/amd-gfx

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 <20201018054332.GB593954@kroah.com>
In-Reply-To: <20201018054332.GB593954@kroah.com>
From: Nick Desaulniers <ndesaulniers@google.com>
Date: Mon, 19 Oct 2020 12:42:15 -0700
Message-ID: <CAKwvOdkR_Ttfo7_JKUiZFVqr=Uh=4b05KCPCSuzwk=zaWtA2_Q@mail.gmail.com>
Subject: Re: [RFC] treewide: cleanup unreachable breaks
To: Tom Rix <trix@redhat.com>
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 clang-built-linux <clang-built-linux@googlegroups.com>,
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 nouveau@lists.freedesktop.org, storagedev@microchip.com,
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 linux-nvdimm <linux-nvdimm@lists.01.org>,
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 MPT-FusionLinux.pdl@broadcom.com, linux-media@vger.kernel.org,
 linux-serial@vger.kernel.org, linux-nfc@lists.01.org, linux-pm@vger.kernel.org,
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 linux-gpio@vger.kernel.org, xen-devel@lists.xenproject.org,
 linux-amlogic@lists.infradead.org, openipmi-developer@lists.sourceforge.net,
 platform-driver-x86@vger.kernel.org, linux-integrity@vger.kernel.org,
 Linux ARM <linux-arm-kernel@lists.infradead.org>, linux-edac@vger.kernel.org,
 George Burgess <gbiv@google.com>, Network Development <netdev@vger.kernel.org>,
 linux-usb@vger.kernel.org, linux-wireless <linux-wireless@vger.kernel.org>,
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On Sat, Oct 17, 2020 at 10:43 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Sat, Oct 17, 2020 at 09:09:28AM -0700, trix@redhat.com wrote:
> > From: Tom Rix <trix@redhat.com>
> >
> > This is a upcoming change to clean up a new warning treewide.
> > I am wondering if the change could be one mega patch (see below) or
> > normal patch per file about 100 patches or somewhere half way by collecting
> > early acks.
>
> Please break it up into one-patch-per-subsystem, like normal, and get it
> merged that way.
>
> Sending us a patch, without even a diffstat to review, isn't going to
> get you very far...

Tom,
If you're able to automate this cleanup, I suggest checking in a
script that can be run on a directory.  Then for each subsystem you
can say in your commit "I ran scripts/fix_whatever.py on this subdir."
 Then others can help you drive the tree wide cleanup.  Then we can
enable -Wunreachable-code-break either by default, or W=2 right now
might be a good idea.

Ah, George (gbiv@, cc'ed), did an analysis recently of
`-Wunreachable-code-loop-increment`, `-Wunreachable-code-break`, and
`-Wunreachable-code-return` for Android userspace.  From the review:
```
Spoilers: of these, it seems useful to turn on
-Wunreachable-code-loop-increment and -Wunreachable-code-return by
default for Android
...
While these conventions about always having break arguably became
obsolete when we enabled -Wfallthrough, my sample turned up zero
potential bugs caught by this warning, and we'd need to put a lot of
effort into getting a clean tree. So this warning doesn't seem to be
worth it.
```
Looks like there's an order of magnitude of `-Wunreachable-code-break`
than the other two.

We probably should add all 3 to W=2 builds (wrapped in cc-option).
I've filed https://github.com/ClangBuiltLinux/linux/issues/1180 to
follow up on.
-- 
Thanks,
~Nick Desaulniers

_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic

From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nick Desaulniers <ndesaulniers@google.com>
Date: Mon, 19 Oct 2020 12:42:15 -0700
Subject: [Intel-wired-lan] [RFC] treewide: cleanup unreachable breaks
In-Reply-To: <20201018054332.GB593954@kroah.com>
References: <20201017160928.12698-1-trix@redhat.com>
 <20201018054332.GB593954@kroah.com>
Message-ID: <CAKwvOdkR_Ttfo7_JKUiZFVqr=Uh=4b05KCPCSuzwk=zaWtA2_Q@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
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To: intel-wired-lan@osuosl.org
List-ID: <intel-wired-lan.osuosl.org>

On Sat, Oct 17, 2020 at 10:43 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Sat, Oct 17, 2020 at 09:09:28AM -0700, trix at redhat.com wrote:
> > From: Tom Rix <trix@redhat.com>
> >
> > This is a upcoming change to clean up a new warning treewide.
> > I am wondering if the change could be one mega patch (see below) or
> > normal patch per file about 100 patches or somewhere half way by collecting
> > early acks.
>
> Please break it up into one-patch-per-subsystem, like normal, and get it
> merged that way.
>
> Sending us a patch, without even a diffstat to review, isn't going to
> get you very far...

Tom,
If you're able to automate this cleanup, I suggest checking in a
script that can be run on a directory.  Then for each subsystem you
can say in your commit "I ran scripts/fix_whatever.py on this subdir."
 Then others can help you drive the tree wide cleanup.  Then we can
enable -Wunreachable-code-break either by default, or W=2 right now
might be a good idea.

Ah, George (gbiv@, cc'ed), did an analysis recently of
`-Wunreachable-code-loop-increment`, `-Wunreachable-code-break`, and
`-Wunreachable-code-return` for Android userspace.  From the review:
```
Spoilers: of these, it seems useful to turn on
-Wunreachable-code-loop-increment and -Wunreachable-code-return by
default for Android
...
While these conventions about always having break arguably became
obsolete when we enabled -Wfallthrough, my sample turned up zero
potential bugs caught by this warning, and we'd need to put a lot of
effort into getting a clean tree. So this warning doesn't seem to be
worth it.
```
Looks like there's an order of magnitude of `-Wunreachable-code-break`
than the other two.

We probably should add all 3 to W=2 builds (wrapped in cc-option).
I've filed https://github.com/ClangBuiltLinux/linux/issues/1180 to
follow up on.
-- 
Thanks,
~Nick Desaulniers