Re: Compilation errors

[Stefano Brivio <sbrivio@redhat.com>]

On Fri, 01 Apr 2022 14:01:03 +0200
"Fabio M. De Francesco" <fmdefrancesco@gmail.com> wrote:

> On venerdì 1 aprile 2022 12:13:57 CEST Stefano Brivio wrote:
> > Hi Fabio,
> > 
> > On Fri, 01 Apr 2022 11:35:13 +0200
> > "Fabio M. De Francesco" <fmdefrancesco@gmail.com> wrote:  
> > >
> > > [...]
> > > 
> > > Can someone help me to understand what is happening and how to fix this issue?
> > > Could it depend on a configuration option that, unintentionally enabled, make 
> > > the build fail whenever "case label does not reduce to an integer constant" is 
> > > hit? If so, which option?  
> > 
> > Those would be warnings, but kernel builds switched to -Werror by
> > default a while ago, see commit 3fe617ccafd6 ("Enable '-Werror' by
> > default for all kernel builds") -- meaning that all warnings are
> > treated as errors. You can disable CONFIG_WERROR:
> > 
> > 	scripts/config -d WERROR
> > 
> > to double check.   
> 
> Hi Stefano,
> 
> Thanks for your prompt reply!
> 
> I know that the kernel has switched to -Werror by default. I use a largely 
> customized .config and I can confirm you that CONFIG_WERROR is _not_ enabled:
> 
> xp4ns3@leap> grep CONFIG_WERROR .config  
> # CONFIG_WERROR is not set
> 
> >
> > [...]
> >
> > As to why it started happening for you recently: maybe you just
> > switched to gcc 11 and a newer version of clang? Can you try with
> > gcc 10 if you have it still installed?  
> 
> I had it not anymore installed, so I had to re-install gcc v10. With it
> I ran "make clean && CC=gcc-10 make -j12" but it still triggers the same 
> errors and the build still fails.

Okay, then that's really an error.

> The last output line, just before exit, is:
> 
> make: *** [Makefile:1838: drivers] Error 2
> 
> Furthermore, I want to make you notice that I have no errors when I 
> build Torvald's tree with gcc v11. In fact, I rebuilt it now again and 
> got no failures.
> 
> Why is this issue showing only with staging-testing? I cannot yet see 
> any reasonable explanation.

It might simply be that the you're building some drivers on your
staging tree that you're not building on the mainline tree.

> Any other ideas? If I'm not able to figure out what's happening, I won't
> be able to contribute to staging anymore. Greg (reasonably) requires that
> all the changes get built before sending patches, therefore, this issue
> is a blocker. I'm losing the chance to be selected for the Outreachy
> internship.

You reported this issue three hours ago and, as far as I can tell,
there are 672 hours in four weeks...

> Since I have more or less 100 patches already in Torvald's tree, can I
> be exempted from working on those 10 required patches for staging? 
> Otherwise I could simply send 10 clean-up patches that I can confidently
> send without trying to compile them. Or I can send patches for Torvald's
> tree. I really don't know what to do.

...well, then you could also try to debug this build issue I guess? On
which drivers it happens? You reported two. If you disable those two,
will it still happen? On how many? And what about fixing those cases?

-- 
Stefano