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

Hi Corinna

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

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 :

On May  2 19:14, zosrothko wrote:

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


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.


Attachment: stdio.h.1.patch
Description: Text document

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