Windows 1250 or UTF-8 in MS Visual Studio? - encoding

Question

Here I have a simple, exemplary code in MS Visual Studio:
#include<string>
#include<iostream>
using namespace std;
int main()
{
cout << static_cast<int>('ą') << endl; // -71
return 0;
}
The question is why this cout prints out -71 as if MS Visual Studio was using Windows 1250 if as far as I know it uses UTF-8?

Answer 1

Your source file is saved in Windows-1250, not UTF-8, so the byte stored between the two single quotes is 0xB9 (see Windows-1250 table). 0xB9 taken as a signed 8-bit value is -71.
Save your file in UTF-8 encoding and you'll get a different answer. I get 50309 which is 0xc485. since UTF-8 is a multibyte encoding, it would be better to use modern C++ to output the bytes of an explicit UTF-8 string, use UTF-8 source encoding, and tell the compiler explicitly that the source encoding it UTF-8:
test.c - saved in UTF-8 encoding and compiled with /utf-8 switch in MSVS:
#include<string>
#include<iostream>
#include <cstdint>
using namespace std;
int main()
{
string s {u8"ą马"};
for(auto c : s)
cout << hex << static_cast<int>(static_cast<uint8_t>(c)) << endl;
return 0;
}
Output:
c4
85
e9
a9
ac
Note C4 85 is the correct UTF-8 bytes for ą and E9 A9 AC are correct for Chinese 马 (horse).