Can the `main` Function Recursively Call Itself in C ?

Can main Function Call Itself in C ?

Problem:

The following code compiles without errors but enters an infinite loop:

int main() {
    return main();
}

Answer:

Calling the main function from within itself in C results in undefined behavior. Undefined behavior means that anything can happen, including:

• The program may crash.
• The program may run forever.
• The program may corrupt memory.

The C standard explicitly states that main function must not be named by an expression. When main calls itself, the compiler must issue a diagnostic message and not compile the code.

Despite this standard requirement, some compilers may not issue a diagnostic message and allow the program to compile. However, executing such a program invokes undefined behavior.

Compiler Behavior:

Compilers are not required to enforce all rules of the C standard, including the one prohibiting main from calling itself. They may issue warnings or errors, but the exact behavior varies across different compilers and compiler settings.

Implications:

Calling main recursively is illegal in C . Even if a compiler allows it, the program exhibits undefined behavior and should not be relied upon.

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