RT-Thread 入门学习笔记 - 解决RT_ASSERT失效的问题

发布于 2021-02-19 18:08:37 浏览：3846 订阅该版

[tocm]

[RT-Thread 入门学习笔记 - 目录](https://club.rt-thread.org/ask/article/3420.html)

[RT-Thread 入门学习笔记 - menuconfig Kconfig的使用](https://club.rt-thread.org/ask/article/2427.html)

[RT-Thread 入门学习笔记 - 熟悉动态内存申请与释放](https://club.rt-thread.org/ask/article/2552.html)

[RT-Thread 入门学习笔记 - 查看线程栈的地址](https://club.rt-thread.org/ask/article/2554.html)

[RT-Thread 入门学习笔记 - 解决RT_ASSERT失效的问题](https://club.rt-thread.org/ask/article/2559.html)

[RT-Thread 入门学习笔记 - Keil MDK软件调试排查assert](https://club.rt-thread.org/ask/article/2562.html)

[RT-Thread 入门学习笔记 - 熟悉全局中断的操作](https://club.rt-thread.org/ask/article/2569.html)

## 前言

- 自己在使用动态内存过程中，重复rt_free一个指针，发现竟然没有出错！

- 忽然发现自己的代码异常的健壮，不出现RT_ASSERT断言死机？

- 经过软件调试，发现：自己关闭了 RT_ASSERT功能！！

## 开启RT_ASSERT功能

![2021-02-19_180051.png](https://oss-club.rt-thread.org/uploads/20210219/bf7aca168495e8b8016272dacef362bf.png)

![2021-02-19_180103.png](https://oss-club.rt-thread.org/uploads/20210219/17beff4f33a3aa04625bc62d6d19c7bd.png)

## 分析原因

* 要开启：`#define RT_DEBUG`

* 为什么不开启：`#define RT_DEBUG`，RT_ASSERT就不起作用了呢？

* 原来RT_ASSERT代码的执行，rt_assert_handler，依赖：RT_DEBUG

```
/* rt-thread\src\kservice.c */

#ifdef RT_DEBUG
/* RT_ASSERT(EX)'s hook */

void (*rt_assert_hook)(const char *ex, const char *func, rt_size_t line);

/**
 * This function will set a hook function to RT_ASSERT(EX). It will run when the expression is false.
 *
 * @param hook the hook function
 */
void rt_assert_set_hook(void (*hook)(const char *ex, const char *func, rt_size_t line))
{
    rt_assert_hook = hook;
}

/**
 * The RT_ASSERT function.
 *
 * @param ex the assertion condition string
 * @param func the function name when assertion.
 * @param line the file line number when assertion.
 */
void rt_assert_handler(const char *ex_string, const char *func, rt_size_t line)
{
    volatile char dummy = 0;

if (rt_assert_hook == RT_NULL)
    {
#ifdef RT_USING_MODULE
        if (dlmodule_self())
        {
            /* close assertion module */
            dlmodule_exit(-1);
        }
        else
#endif
        {
            rt_kprintf("(%s) assertion failed at function:%s, line number:%d \n", ex_string, func, line);
            while (dummy == 0);
        }
    }
    else
    {
        rt_assert_hook(ex_string, func, line);
    }
}
RTM_EXPORT(rt_assert_handler);
#endif /* RT_DEBUG */

```
![2021-02-19_180431.png](https://oss-club.rt-thread.org/uploads/20210219/1e6dc89a09c90ebd5cea4b1d363363c1.png)

## 问题解决

```
.config - RT-Thread Configuration
RT-Thread Kernel
    [*] Enable debugging features  ---> 
```

- 使能：#define RT_DEBUG后，RT_ASSERT正常了

![2021-02-19_180711.png](https://oss-club.rt-thread.org/uploads/20210219/791f33f9c5285e7fda66bf1696752b52.png)

- 至于什么时候关闭的这个内核选项，不清楚了，遇到问题，多请教，多调试，多总结。