Re: [PATCH 6/7] Compiler Attributes: remove unneeded sparse (__CHECKER__) tests

[Luc Van Oostenryck]

On Fri, Aug 31, 2018 at 11:55:51PM +0200, Miguel Ojeda wrote:
> Hi Nick,
> 
> On Fri, Aug 31, 2018 at 11:38 PM, Nick Desaulniers
> <ndesaulniers@xxxxxxxxxx> wrote:
> > On Fri, Aug 31, 2018 at 10:05 AM Miguel Ojeda
> > <miguel.ojeda.sandonis@xxxxxxxxx> wrote:
> >>
> >> Sparse knows about a few more attributes now, so we can remove
> >> the __CHECKER__ conditions from them (which, in turn, allow us
> >> to move some of them later on to compiler_attributes.h).
> >>
> >>   * assume_aligned: since sparse's commit ffc860b ("sparse:
> >>     ignore __assume_aligned__ attribute"), included in 0.5.1
> >>
> >>   * error: since sparse's commit 0a04210 ("sparse: Add 'error'
> >>     to ignored attributes"), included in 0.5.0
> >>
> >>   * hotpatch: since sparse's commit 6043210 ("sparse/parse.c:
> >>     ignore hotpatch attribute"), included in 0.5.1
> >>
> >>   * warning: since sparse's commit 977365d ("Avoid "attribute
> >>     'warning': unknown attribute" warning"), included in 0.4.2
> >>
> >> Cc: Eli Friedman <efriedma@xxxxxxxxxxxxxx>
> >> Cc: Christopher Li <sparse@xxxxxxxxxxx>
> >> Cc: Kees Cook <keescook@xxxxxxxxxxxx>
> >> Cc: Ingo Molnar <mingo@xxxxxxxxxx>
> >> Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
> >> Cc: Arnd Bergmann <arnd@xxxxxxxx>
> >> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> >> Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
> >> Cc: Joe Perches <joe@xxxxxxxxxxx>
> >> Cc: Dominique Martinet <asmadeus@xxxxxxxxxxxxx>
> >> Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
> >> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
> >> Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@xxxxxxxxx>
> >> ---
> >>  include/linux/compiler-gcc.h   | 6 ++----
> >>  include/linux/compiler_types.h | 2 +-
> >>  2 files changed, 3 insertions(+), 5 deletions(-)
> >>
> >> diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h
> >> index fdf2fbe6d544..32e6ce06163f 100644
> >> --- a/include/linux/compiler-gcc.h
> >> +++ b/include/linux/compiler-gcc.h
> >> @@ -84,14 +84,12 @@
> >>
> >>  #define __compiletime_object_size(obj) __builtin_object_size(obj, 0)
> >>
> >> -#ifndef __CHECKER__
> >>  #define __compiletime_warning(message) __attribute__((warning(message)))
> >>  #define __compiletime_error(message) __attribute__((error(message)))
> >>
> >> -#ifdef LATENT_ENTROPY_PLUGIN
> >> +#if defined(LATENT_ENTROPY_PLUGIN) && !defined(__CHECKER__)
> >>  #define __latent_entropy __attribute__((latent_entropy))
> >>  #endif
> >> -#endif /* __CHECKER__ */
> >>
> >>  /*
> >>   * calling noreturn functions, __builtin_unreachable() and __builtin_trap()
> >> @@ -139,7 +137,7 @@
> >>
> >>  /* gcc version specific checks */
> >>
> >> -#if GCC_VERSION >= 40900 && !defined(__CHECKER__)
> >> +#if GCC_VERSION >= 40900
> >>  /*
> >>   * __assume_aligned(n, k): Tell the optimizer that the returned
> >>   * pointer can be assumed to be k modulo n. The second argument is
> >> diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h
> >> index 3662b19599fc..5dddc7e0c607 100644
> >> --- a/include/linux/compiler_types.h
> >> +++ b/include/linux/compiler_types.h
> >> @@ -216,7 +216,7 @@ struct ftrace_likely_data {
> >>  #define __must_check
> >>  #endif
> >>
> >> -#if defined(CC_USING_HOTPATCH) && !defined(__CHECKER__)
> >> +#if defined(CC_USING_HOTPATCH)
> >>  #define notrace                        __attribute__((hotpatch(0, 0)))
> >>  #else
> >>  #define notrace                        __attribute__((no_instrument_function))
> >> --
> >> 2.17.1
> >>
> >
> > Everything looks correct here.  It would be good for the sparse
> > maintainer to triple check the commit sha's (as those are for sparse's
> > code base, not the kernel's) and have their blessing.  If Chris is
> 
> Actually, nowadays it is very easy to check in sparse's
> gcc-attr-list.h file, but since the file was not always there, I tried
> to find out when the support for each attribute was added.

Acked-by: Luc Van Oostenryck <luc.vanoosternyck@xxxxxxxxx>