Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1650198

Re: [patch] compiler, clang: suppress warning for unused static inline functions

Show all headers | View raw

* Matthias Kaehlcke <mka@chromium.org> wrote:

> El Wed, May 24, 2017 at 02:01:15PM -0700 David Rientjes ha dit:
> 
> > GCC explicitly does not warn for unused static inline functions for
> > -Wunused-function.  The manual states:
> > 
> > 	Warn whenever a static function is declared but not defined or
> > 	a non-inline static function is unused.
> > 
> > Clang does warn for static inline functions that are unused.
> > 
> > It turns out that suppressing the warnings avoids potentially complex
> > #ifdef directives, which also reduces LOC.
> > 
> > Supress the warning for clang.
> > 
> > Signed-off-by: David Rientjes <rientjes@google.com>
> > ---
> 
> As expressed earlier in other threads, I don't think gcc's behavior is
> preferable in this case. The warning on static inline functions (only
> in .c files) allows to detect truly unused code. About 50% of the
> warnings I have looked into so far fall into this category.
> 
> In my opinion it is more valuable to detect dead code than not having
> a few more __maybe_unused attributes (there aren't really that many
> instances, at least with x86 and arm64 defconfig). In most cases it is
> not necessary to use #ifdef, it is an option which is preferred by
> some maintainers. The reduced LOC is arguable, since dectecting dead
> code allows to remove it.

Static inline functions in headers are often not dead code.

Thanks,

	Ingo

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[patch] compiler, clang: suppress warning for unused static inline  functions David Rientjes <rientjes@google.com> - 2017-05-24 23:10 +0200
  Re: [patch] compiler, clang: suppress warning for unused static  inline functions Matthias Kaehlcke <mka@chromium.org> - 2017-05-24 23:30 +0200
    Re: [patch] compiler, clang: suppress warning for unused static  inline functions Andrew Morton <akpm@linux-foundation.org> - 2017-05-24 23:40 +0200
      Re: [patch] compiler, clang: suppress warning for unused static  inline functions Doug Anderson <dianders@chromium.org> - 2017-05-25 01:30 +0200
        Re: [patch] compiler, clang: suppress warning for unused static  inline functions David Rientjes <rientjes@google.com> - 2017-05-31 02:20 +0200
          Re: [patch] compiler, clang: suppress warning for unused static  inline functions Matthias Kaehlcke <mka@chromium.org> - 2017-05-31 04:00 +0200
          Re: [patch] compiler, clang: suppress warning for unused static  inline functions Doug Anderson <dianders@chromium.org> - 2017-05-31 18:00 +0200
            Re: [patch] compiler, clang: suppress warning for unused static  inline functions Mark Brown <broonie@kernel.org> - 2017-05-31 20:30 +0200
            Re: [patch] compiler, clang: suppress warning for unused static  inline functions David Rientjes <rientjes@google.com> - 2017-05-31 23:50 +0200
              Re: [patch] compiler, clang: suppress warning for unused static  inline functions Doug Anderson <dianders@chromium.org> - 2017-06-01 00:40 +0200
                Re: [patch] compiler, clang: suppress warning for unused static  inline functions Matthias Kaehlcke <mka@chromium.org> - 2017-06-01 02:10 +0200
    Re: [patch] compiler, clang: suppress warning for unused static  inline functions Ingo Molnar <mingo@kernel.org> - 2017-05-25 08:00 +0200
      Re: [patch] compiler, clang: suppress warning for unused static  inline functions Matthias Kaehlcke <mka@chromium.org> - 2017-05-25 18:20 +0200
        Re: [patch] compiler, clang: suppress warning for unused static  inline functions Joe Perches <joe@perches.com> - 2017-05-25 18:50 +0200
          Re: [patch] compiler, clang: suppress warning for unused static  inline functions Matthias Kaehlcke <mka@chromium.org> - 2017-05-25 20:00 +0200

csiph-web