g++ Locale ?? correction

[Liu Hao]

On 2017/5/4 0:04, Papa wrote:
> Yes, absolutely right. That's what I thought as well.
> Now, who should look at this problem, MinGW64 or Gnu, who should I
> contact to report this bug?
Please make sure it is really a bug before submitting it, by printing 
the first byte of the string in question in your second example, in 
order to make sure it is really a null-terminator 
(`--enable-fully-dynamic-string` may cause trouble here, see PR16612):

```c++
void jme::Locale::setGlobalLocale(const std::string& str){
       std::string tmp;
       __builtin_printf("str[0] = %d\n", str.data()[0]);
       tmp = std::setlocale(LC_ALL, str.data() );
}
```

I ask this mostly because the function `setlocale()` is provided by 
MSVCRT and is totally opaque to MinGW-w64. And I can't reproduce the 
problem:

```plaintext
E:\Desktop>cat test.cc
#include <iostream>
#include <string>
#include <clocale>

void my_set_locale_1(const std::string &str){
         auto p = std::setlocale(LC_ALL, "");
         std::cout <<__func__ <<": p = " <<p <<std::endl;
}
void my_set_locale_2(const std::string &str){
         auto p = std::setlocale(LC_ALL, str.data());
         std::cout <<__func__ <<": p = " <<p <<std::endl;
}

int main(){
         my_set_locale_1({ });
         my_set_locale_2({ });
}

E:\Desktop>g++ test.cc -Wall -Wextra -Wpedantic -std=c++11
test.cc: In function 'void my_set_locale_1(const string&)':
test.cc:5:41: warning: unused parameter 'str' [-Wunused-parameter]
  void my_set_locale_1(const std::string &str){
                                          ^~~

E:\Desktop>a.exe
my_set_locale_1: p = Chinese (Simplified)_People's Republic of China.936
my_set_locale_2: p = Chinese (Simplified)_People's Republic of China.936

E:\Desktop>
```

-- 
Best regards,
LH_Mouse