what is the cause of the segmentation violation in this case?

This is the follow-up question from here

I'm trying to inferface matlab with Cadence Spectre (a type of Spice used for electronic ciricuit simulation). There is a SPECTRE/RF Matlab Toolbox that enables interfacing between MATLAB and Spectre using a bundle of function.

with some helps from the original question, I succeeded to link dynamic libraries to Matlab by using LD_LIBRARY_PATH. However, there was another issue that caused Matlab crash, and in the crash log it reported 'segmentation violation'

is there any way that I could do to find out the cause of it?

some of log is below

This error was detected while a MEX-file was running. If the MEX-file

is not an official MathWorks function, please examine its source code

for errors. Please consult the External Interfaces Guide for information

on debugging MEX-files.

[dpb]

There's nothing anybody here could do without the mex file code and input to try to run it; as noted in the other thread, this now is no longer really a MATLAB Q? but more appropriate for the users' support group and the vendor site.

However, the first thing to do is to make sure you can run the sample problem(s) that came with the code to ensure proper installation (it DID come with test/examples datasets, right?).

Next, study the documentation THOROUGHLY to be sure you've trying to use it correctly; as also noted in other thread comments, a prime way to crash a MEX file that isn't as robust as it might be is to pass the wrong data type to one or more of the arguments.

[Jongsung Park]

@dpb

Thanks for leaving a comment again. As you advised at the previous thread, I tried to resolve this issu with local EDA tool support center(not exactly, but one of roles of that institution is to help EDA tool users with setting up this kind of environment) . Actually, it could be much better if I was able to use Cadence customer support, but then I would have to reach to my linux server administrator for license information, since Cadence assistance requires it. which takes some time. The staff of local center noted that using spectre/RF Matlab Toolbox in MATLAB 2022b version is not compatible with any version of Spectre, let alone my version of spectre releasesd 5 years ago. he suggested that downloading a little bit older version of MATLAB could resolve the issue.

I will leave a comment again if this suggestion solves the error

[Jongsung Park]

@dpb

I solved the issue by downgrading Matlab version from R2022b to R2018a.

The key is to reduce the gap between the release date of Matlab version to the one of Spectre(Or, MMSIM) version that I am using. My version of Spectre was releasesd around Sept.2018, therefore I reinstalled Matlab as R2018a version. Then it worked.

Thanks for consulting me. i really appreciate it! Is it okay to self-answer my question?

Answer 1

[Aditya Srikar]

Hi Jongsung Park

If a binary MEX file causes a segmentation violation or assertion, it means that the MEX file attempted to access some unallocated segment of memory. The common cause of segmentation violation is passing a null pointer to a function.

To troubleshoot such kind of issues, run MATLAB within a debugging environment. Also you can try using older versions of MATLAB to match the version of the toolboxes you have used in the program.

Hope it helps !