Geek asks and answers

Why don't standard let functions return compilation?

f () is not returned, even if the signature should say. Why is there a reason to compile it? Is there a reason why the C standard does not require a compiler error?

I know that this is Undefined behavior and that’s all, but why is it allowed in the first place? Is there a historical reason?

double f(){}

int main()
{
    f();
    return 0;
}
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4 answers

Is there a reason why the C standard does not require the compiler to make it not work?

By invoking undefined behavior, the C standard allowed compilers to be less complex. Indeed, there are some cases, for example, expressions ifin which it is difficult to say whether a function returns a value or not:

int f(int n)
{
  if (n > 0) return 1;
}
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double f() {
    if (g()) exit();
}

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