Default return value of a boolean type return function in c++ [duplicate]

This question already has answers here: 开发者_开发问答 Closed 11 years ago.

Possible Duplicate:

Why can you return from a non-void function without returning a value without producing a compiler error?

According to the c++ standard what should be the return value of the following function.

bool done()
{
     // no return value
}

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This would be undefined behavior - anything can happen.

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Although it returns a value, it is undefined.