resetting timer0 interrupt flag

[foTONICS]

So I was reading up on embedded C programming for the PIC and came across this code that uses the overflow flag of timer0 to trigger an interrupt. But don't you need to clear the flag before you exit the ISR, or does the compiler insert that bit of code by itself?

I've attached a screenshot of said code:

 

[(*steve*)]

I would be looking at the set_timer0() function. Does that clear the interrupt as a side-effect?

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