Re: [PATCH 1/3] MdePkg: add RETURNS_TWICE attribute

[Michael Zimmermann <sigmaepsilon92@gmail.com>]

Liming:
The other macros have comments both before the compiler directives and
before each define for each compiler.
To me it looks like these are slightly differently formulated only and
kinda redundant too.
Is there a rule or do you have suggestions for writing comments for this
kind of macro?

On Mon, Dec 25, 2017 at 4:11 AM, Gao, Liming <liming.gao@intel.com> wrote:

> Micha:
>    Could you add comments for new macro RETURNS_TWICE like others, such as
> ANALYZER_NORETURN?
>
> >-----Original Message-----
> >From: Ard Biesheuvel [mailto:ard.biesheuvel@linaro.org]
> >Sent: Friday, December 22, 2017 11:24 PM
> >To: M1cha <sigmaepsilon92@gmail.com>
> >Cc: edk2-devel@lists.01.org; Kinney, Michael D
> ><michael.d.kinney@intel.com>; Gao, Liming <liming.gao@intel.com>
> >Subject: Re: [edk2] [PATCH 1/3] MdePkg: add RETURNS_TWICE attribute
> >
> >On 22 December 2017 at 07:23, M1cha <sigmaepsilon92@gmail.com> wrote:
> >> Contributed-under: TianoCore Contribution Agreement 1.1
> >> Signed-off-by: Michael Zimmermann <sigmaepsilon92@gmail.com>
> >> ---
> >>  MdePkg/Include/Base.h | 10 ++++++++++
> >>  1 file changed, 10 insertions(+)
> >>
> >> diff --git a/MdePkg/Include/Base.h b/MdePkg/Include/Base.h
> >> index 22ab5d3715fb..c863de407418 100644
> >> --- a/MdePkg/Include/Base.h
> >> +++ b/MdePkg/Include/Base.h
> >> @@ -218,6 +218,16 @@ VERIFY_SIZE_OF (__VERIFY_UINT32_ENUM_SIZE,
> >4);
> >>    #endif
> >>  #endif
> >>
> >> +#ifndef RETURNS_TWICE
> >> +  #if defined (__GNUC__) || defined (__clang__)
> >> +    #define RETURNS_TWICE  __attribute__((returns_twice))
> >> +  #elif defined(_MSC_EXTENSIONS) && !defined(MDE_CPU_EBC)
> >> +    #define RETURNS_TWICE
> >> +  #else
> >> +    #define RETURNS_TWICE
> >
> >What is the point of having two versions that are #defined to nothing?
> >
> >> +  #endif
> >> +#endif
> >> +
> >>  //
> >>  // For symbol name in assembly code, an extra "_" is sometimes
> necessary
> >>  //
> >> --
> >> 2.15.1
> >>
>