c++11 - strange behaviour of this c++ piece of code (std::wcout and std::exception) -

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• mixing cout , wcout in same program 5 answers

i'm working piece of code , i've found method doesn't throw exception after succesfull call. if use std::cout fine , exception thrown. i'm using gcc version 4.9.2 (debian 4.9.2-10). gcc bug or stl bug code problem or else?

// exceptions #include <iostream> using namespace std; class c {    public:     string srch(int &i) {         if (i == 0) {   //found             wcout << "got it: " << << endl; return "i";         }        throw std::exception();      }   };   int main () {    c c = c();    int = 2;    int j = 0;    try    {      c.srch(j);      c.srch(i);    }    catch (const std::exception &e) {      cout << "an exception occurred. exception nr. " << e.what() << '\n';    }     return 0;  } 

here's ideone link reproduce lack of exception wcout. , a link reproducing exception when cout used.

your example does not prove exception wasn't thrown.

the cout message in catch block not displayed, because used wcout , mixing character widths on same device (stdout) undefined behaviour.

change cout wcout , you'll see exception was thrown, didn't see message expected.