Re: stdio.h patches for g++ -std=c++11

[zosrothko <zosrothko at orange dot fr>]

Hi Corinna

Here the patch as you required. All  stdio c++11functions only functions 
are grouped in the beginning of the block.

zos
Le 08/05/2014 10:22, Corinna Vinschen a Ãcrit :
> On May  8 06:22, zosrothko wrote:
> > Hi Corinna
> > Le 05/05/2014 14:54, Corinna Vinschen a Ãcrit :
> > > Hi,
> > >
> > > On May  2 19:14, zosrothko wrote:
> > > > Hi
> > > >
> > > > This is a patch for exposing the new stdio functions added by the
> > > > c++11 standard. Without this patch the snprintf for example is not
> > > > exposed as
> > > >
> > > > $ cat hello.cpp
> > > > #include <cstdio>
> > > >
> > > > int main(int argc, char** argv) {
> > > > char buf[24];
> > > > snprintf(buf, 2, "", 2);
> > > > return 0;
> > > > }
> > > >
> > > > $ g++ -std=c++11 hello.cpp
> > > > hello.cpp: In function âint main(int, char**)â:
> > > > hello.cpp:4:30: erreur: âsnprintfâ was not declared in this scope
> > > > snprintf("", 2, "", 2);
> > > >
> > > > $ g++ -xc++ -std=c++11 -dM -E - < /dev/null | sort | grep ANSI
> > > > #define __STRICT_ANSI__ 1
> > > >
> > > > $ g++ -dM -E - < /dev/null | sort | grep ANSI
> > > >
> > > > $
> > > >
> > > > Regards
> > > I applied a simpler patch which just enables the C99 printf/scanf
> > > functions for C++11 using the already existing declaration block.
> > I have just checked out the stdio.h with the patch you made but IMO,
> > it is not correct. the c++11 standard allows only the functions
> > snprintf, vfscanf, vscanf, vsnprintf, and vsscanf. The patch you
> > applied will allow all other functions from the existing declaration
> > block. This patch will allow a c++ developper to use non standard
> > c++11 functions which will preclude the portability of the code on
> > another system where the strict adherence will be in place.
> >
> > Thus, could you rollback your change and applies the original patch.
> The original patch has the downside that it adds double function
> declarations.  This is not feasible or, at least, it's not what we do in
> any other header file.
>
> If you want to make sure only these functions are declared, it has to be
> done using matching #if expressions guarding the existing declarations.
>
>
> Corinna

Attachment: stdio.h.1.patch
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