使用指针从数组中获取数据越界后不会有提示，血泪教训
本帖最后由 地瓜patch 于 2025-4-19 17:25 编辑uint8_t data1; for(uint8_t x = 0; x < 8; x++)
{
data1 = 0;
}当在超出数组限制的 count 循环中使用数组时，编译器可以报错warning: iteration 5 invokes undefined behavior但是如果使用指针，编译器可能不会发出警告，并且程序可能会进入无限循环：CH10 data1 = 10
CH10 data1 = 10
CH10 data1 = 10
CH10 data1 = 10
CH10 data1 = 10
CH10 data1 = 10
CH10 data1 = 10导致循环的代码：/* USER CODE BEGIN 0 */
uint8_t foo1(uint8_t *data2)
{
uint8_t data3;
foo2(data3, 0);
*data2 = data3;
return 0;
}
uint8_t foo2(uint8_t* data4, uint8_t channel)
{
for (uint8_t i = 0; i < 9; i++)
{
data4 = 10;
}
return 0;
}
/* USER CODE END 0 */
/* USER CODE BEGIN 2 */
for(uint8_t x = 0; x < 8; x++)
{
uint8_t data1 = 0;
foo1(&data1);
UsrLog("CH%d data1 = %d", x, data1);
HAL_GPIO_TogglePin(LED_GPIO_Port, LED_Pin);
HAL_Delay(500);
}
/* USER CODE END 2 */请注意，函数 foo1 传递一个 array，函数 foo2 尝试处理一个包含 9 个元素的数组。uint8_t foo1(uint8_t *data2)
{
uint8_t data3; <-------- limit: 8
foo2(data3, 0);
*data2 = data3;
return 0; // error
}
uint8_t foo2(uint8_t* data4, uint8_t channel)
{
for (uint8_t i = 0; i < 9; i++) <----- limit: 9
{
data4 = 10;
}
return 0;
}
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