Gcc function call semantics for mismatch signature in caller / callle

Question

I discovered something strange in gcc and hope to get some input, whether it's a feature or a quirk.
 Essentially, I have a function defined in func.c as

void f(int a, int b, FILE* f)  
{  
   ...  
   ...  
} 

There is no corresponding header file. But does gcc give no warning when I call f (a, b) and gdb shows me that f is called with three parameters? Why is this so ?. What is semantics for filling in the third argument.

Answer 1

f() , , f() int .

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