无限循环中的返回语句 [英] Return statement in an infinite loop

问题描述

如果这个 return 语句在这个无限的 while(1) 循环中，它会返回到哪里?更重要的是，我不知道 while(1) 循环会被破坏???

Where does this return statement return to if it is inside this infinite while(1) loop? More importantly, I had no idea that a while(1) loop could be broken???

void __attribute__((interrupt, no_auto_psv)) _T3Interrupt(void)
{
int count;

    IFS0bits.T3IF = 0;          // clear Tmr3 interrupt flag

    StopMotor();
    IEC0bits.ADIE = 0;          // disable ADC interrupt
    IEC0bits.CNIE = 0;          // disable CN interrupt
    IEC0bits.T3IE = 0;          // disable Tmr3 interrupt

    T3CONbits.TON = 1;          // restart tmr3
    count = 0;

    while (1)
    {
        if (IFS0bits.T3IF)
        {
            IFS0bits.T3IF = 0;  // clear flag
            if (count++ >= RESTART_COUNT)
            {
                IEC0bits.ADIE = 1;          // enable ADC interrupt
                IEC0bits.CNIE = 1;          // enable CN interrupt
                T3CONbits.TON = 0;          // stop tmr3
                IEC0bits.T3IE = 1;          // enable Tmr3 interrupt
                return;
            }
        }
    }
    return;
}

推荐答案

所有的 return 语句都会返回到函数被调用的地方，不管它们在函数中的什么位置.

All return statements will return to wherever the function was called from, regardless of where they are located within the function.

例如，如果我写:

int main()
{
    _iT3Interrupt();

}

那么_iT3Interrupt中的return语句会将控制流恢复到main.

Then the return statement in _iT3Interrupt will revert control flow back to main.

此外，any 循环可以通过以下任何一种方式退出(即使条件是 1、true 或其他等价物)构造:

Also, any loop can be exited (even if the condition is 1, true, or some equivalent) with any of the following constructs:

break; //exits the loop

return; //exits the function, thus ending the loop

goto <label-outside-loop>; //self-explanatory

exit(); abort(); //exits the program. Bit of a stretch to say that this ends the loop...

而在 C++ 中，throw 会展开堆栈，直到它到达相应的 catch，从而退出函数.C setjmp 和 longjmp 函数在这里也可能适用，但我对 C 的了解还不够，无法确定它们的用法.

And in C++, throw, which will unwind the stack until it reaches a corresponding catch, thus exiting the function. The C setjmp and longjmp functions may also be applicable here, but I don't know enough C to be certain of their usage.

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