#295 _pformat does not support %zd of C99

[Ray Linn]

in C99 ,%zd is used to print the size_t, for example

#include <stdio.h>
#include <string.h>
int main(void)
{
int a =1;
char b[4] ="aaa";
printf("%zd %zd %lu\n",sizeof a,sizeof(int),sizeof a);
printf("%zd %zd\n",sizeof b,strlen(b));
return 0;
}

gcc -std=c99 foo.c -o foo.exe

looks current 2.0.2 runtime does not support this format, and only characters 'zd' is print out. has this been fixed on 2.0.3

[Ray Linn]

This issue is related with sprintf "%zd" format which is a C99 feature.
To enable sprintf "%zd" format, Ruby 1.9.3 defines macro _GNU_SOURCE.
If _GNU_SOURCE is defined, MinGW32 defines __USE_MINGW_ANSI_STDIO macro.
But MinGW64 ignores _GNU_SOURCE macro.

The workaround is define macro __USE_MINGW_ANSI_STDIO like this:
./configure --build=x86_64-w64-mingw32 CFLAGS="-O2 -finline-functions -D__USE_MINGW_ANSI_STDIO"

I am not sure this is a bug, but I found MinGW64 cannot handle -std=c99 flag in this case.

Consider this:

C:\work>type foo.c
#include <stdio.h>
int main()
{
printf("%zd",(size_t)10);
return 0;
}

C:\work>gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=c:/mingw47/mingw/bin/../libexec/gcc/i686-pc-mingw32/4.7.0/lt
o-wrapper.exe
Target: i686-pc-mingw32
Configured with: ../src/configure --prefix=/c/temp/gcc/dest --with-gmp=/c/temp/g
cc/gmp --with-mpfr=/c/temp/gcc/mpfr --with-mpc=/c/temp/gcc/mpc --enable-language
s=c,c++ --with-arch=i686 --with-tune=generic --disable-libstdcxx-pch --disable-n
ls --disable-shared --disable-sjlj-exceptions --disable-win32-registry --enable-
checking=release --enable-lto
Thread model: win32
gcc version 4.7.0 (GCC)

C:\work>gcc -std=c99 foo.c -ofoo.exe

C:\work>foo
10

C:\work>gcc -D_GNU_SOURCE foo.c -ofoo.exe

C:\work>foo
10

C:\work>gcc -D__USE_MINGW_ANSI_STDIO foo.c -ofoo.exe

C:\work>foo
10

C:\work>gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=c:/mingw64_7/bin/../libexec/gcc/x86_64-w64-mingw32/4.7.0/lto
-wrapper.exe
Target: x86_64-w64-mingw32
Configured with: ../gcc-4.7.0/configure --build=x86_64-w64-mingw32 --enable-targ
ets=all --disable-multilib --enable-64bit --prefix=/mingw64 --with-sysroot=/ming
w64 --disable-shared --enable-static --disable-nls --enable-version-specific-run
time-libs --disable-win32-registry --without-dwarf2 --enable-sjlj-exceptions --e
nable-fully-dynamic-string --enable-languages=c,ada,lto,c++,objc,obj-c++,fortran
--enable-libgomp --enable-lto --enable-libssp -enable-gnattools --disable-boots
trap --with-gcc --with-gnu-as --with-gnu-ld --with-stabs --enable-interwork --wi
th-mpfr-include=/home/beta/gcc-build/../gcc-4.7.0/mpfr/src --with-mpfr-lib=/home
/beta/gcc-build/mpfr/src/.libs
Thread model: win32
gcc version 4.7.0 (GCC)

C:\work>gcc -std=c99 foo.c -ofoo.exe

C:\work>foo
zd

C:\work>gcc -D_GNU_SOURCE foo.c -ofoo.exe

C:\work>foo
zd

C:\work>gcc -D__USE_MINGW_ANSI_STDIO foo.c -ofoo.exe

C:\work>foo
10

[Ozkan Sezer]

> has this been fixed on 2.0.3
No. The only difference between 2.0.2 and 2.0.3 is some psdk header fixes

> MinGW64 ignores _GNU_SOURCE macro
I remember suggesting to define __USE_MINGW_ANSI_STDIO when _GNU_SOURCE is defined some years ago and even made a commit but it was decided not to support that and the commit was reverted, can't remember why. Here are the relevant svn commits, 1395 and 1398:
http://mingw-w64.svn.sourceforge.net/viewvc/mingw-w64?view=revision&revision=1395
http://mingw-w64.svn.sourceforge.net/viewvc/mingw-w64?view=revision&revision=1398

Kai?

[Kai Tietz]

This bug report is invalid. The option '-std=c99' just affects the compiler, not the runtime-function used. This is controlled by the switch - I begin to hate this define's name as it is too long ;) - __USE_MINGW_ANSI_STDIO. Please compile your test with additional option '-D__USE_MINGW_ANSI_STDIO=1' and you will see it works as desired.

Close this bug as invalid.