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问题

在使用matlab的csfunction编程时出现了错误：matlab调用.mex函数时，第一次调用正常，第二次调用出现matlab闪退、或者卡死无反应的错误，然后崩溃信息提示堆损坏。然而matlab没有如vs那样方便的编辑器和调试器，因此在找错误的时候非常困难。

问题分析

1. 猜想可能是数组越界等导致的内存问题，然后在网上找到这样一篇文章：
   
   有关奇葩的mex编程时的matlab出现栈内存错误的问题
   
   ，大致分析了出错的原因。
2. matlab提供的调试器功能有限，可以借助第三方软件进行调试，matlab的官方文档内介绍了有关debug C mex S-Functions的技巧和方法。

解决措施

官方文档内介绍：

Debugging C MEX S-Functions Using the Microsoft Visual C++ .NET Environmen Before beginning the example, save the files sfcndemo_timestwo and timestwo.c into your working folder.

1. Open the Simulink model sfcndemo_timestwo.c
2. Create a version of the MEX file that you can debug by compiling the C file using the mex command with the -g option.
   
   
   
   mex -g timestwo.c
   
   
   
   The -g option creates the executable timestwo.mexw32 with debugging symbol included. At this point, you may want to simulate the sfcndemo_timestwo model to ensure it runs properly.
3. Without exiting the MATLAB environment, start the Microsoft Development Environment.
4. From the Microsoft Development Environment menu bar, select Tools > Debug Processes.
5. In the Processes dialog box that opens, select the MATLAB.exe process in the Available Processes list and click Attach.
6. In the Attach to Process dialog box that opens, select Native in the list of program types and click OK. You should now be attached to the MATLAB process.
7. Click Close on the Processes dialog box.
8. Clear the MEX functions in MATLAB using the clear command.
   
   
   
   clear mex
   
   
9. From the Microsoft Development Environment File menu, select Open > File.Select the timestwo.c source files from the file browser that opens.
10. Set a breakpoint on the desired line of code by right-clicking on the line and selecting.Insert Breakpoint from the context menu. If you have not previously run the model, the breakpoint may show up with a question mark, indicating that the executable is not loaded. Subsequently running the model loads the .mexw32 file and removes the question mark from the breakpoint.
11. Start the simulation from the sfcndemo_timestwo Simulink model. You should be running the S-function in the Microsoft Development Environment and can debug the file within that environment.

按照上述方法可以在vs内对C Mex function程序进行调试，查看数组越界情况，最终找到问题所在。