Why does int vs bool typecheck fail

Question

I recently wrongly declared an int as a bool and got no type error from the g++ compiler. Then I tried it again for testing and it compiles fine. Can someone explain why this is acceptable behaviour? Shouldn't the compiler give me a warning at least when i try to ++ a boolean or when i assign a bool as integer.

int main(int argc, char** argv)
{
    bool x = 0;
    x++;
    x++;
    cout << x << "\n";
    return 0;
}

`bool` is internally implemented as an `int` in C++, and the only allowed values are `1` and `0`. — CinCout, Mar 22 '16 at 06:24
@HappyCoder That doesn't sound right. You may be thinking of C. — juanchopanza, Mar 22 '16 at 07:11
Oh yeah. That would be C. In case of C++, implementation varies from compiler-to-compiler — CinCout, Mar 22 '16 at 08:07

mustafagonul · Answer 1 · 2016-03-22T06:31:10.587

1

With the old standards (C++98) it is not an error.
With the new standards incrementing a boolean is deprecated. (C++11)
You can use incrementation on a boolean until C++17.

edited Mar 22 '16 at 06:31

answered Mar 22 '16 at 06:24

mustafagonul

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Why does int vs bool typecheck fail

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