Why does MATLAB hang or produce a segmentation violation when I use Real-Time Workshop to build a Simulink model which has a Simulink Parameter with a long character array?

Why does MATLAB hang or produce a segmentation violation when I use Real-Time Workshop to build a Simulink model which has a Simulink Parameter with a long character array?

I am using a Simulink Parameter in my model, which contains a long character array (>1000 characters). When I build my model, MATLAB will either hang or produce a segmentation violation:

 Stack Trace:

   [0] libmx.dll:_mxGetNChars(0x2fbbe028, 0x3041d6c8 "[struct('block',['autocode3/Diff..", 3543, 0x2fbbe028) + 42 bytes

   [1] libmx.dll:_mxGetString(0, 0x3041d6c8 "[struct('block',['autocode3/Diff..", 3544, 0x2fbbe028) + 70 bytes

   [2] simulink.dll:_BdWriteMxArrayProperty(0x00df6c48, 0x2992aad0 "DefnBlocks_AtSource", 0x2fbbe028, 0x00df6c48) + 432 bytes

   [3] simulink.dll:struct slErrMsg_tag * __cdecl BdWriteUDDProperties(struct BdWriteInfo_Tag *,class UDInterface *,class UDInterface *,int)(0x00df6c48, 0x2ed79090, 0x2fbbe028, 24) + 913 bytes

   [4] simulink.dll:struct slErrMsg_tag * __cdecl BdWriteUDDObjectWithRecursion(struct BdWriteInfo_Tag *,class UDInterface *,int)(0x00df6c48, 0x0ab75a88, 25, 0x00df6ba8 "Àkß") + 188 bytes

   [5] simulink.dll:_BdWriteUDDObject(0x00df6c48, 0x2ed79090, 0x00df6bfc, 0) + 18 bytes

   [6] simulink.dll:struct slErrMsg_tag * __cdecl WriteModelParameters(struct RTWInfo_tag *)(0x00df6bfc, 0x00df6bfc, 0, 0x2fe4a2d8) + 2500 bytes

   [7] simulink.dll:struct slErrMsg_tag * __cdecl WriteRTWFile(struct RTWInfo_tag *)(0x2fe4a2d8, 0x00df6d44 "\mß", 2, 0x7a8a74e8) + 794 bytes

   [8] simulink.dll:void __cdecl DoRTWGen(struct RTWInfo_tag *,int,struct mxArray_tag * * const)(0x00df6bfc, 2, 0x00df6d80, 2) + 600 bytes

   [9] simulink.dll:_sleRTWGen(2, 0x00df6d80, 9, 0x00df6e48) + 140 bytes

Answer 1

[MathWorks Support Team]

This bug has been fixed for Release 14 (R14). For previous releases, please read below for any possible workarounds:

This has been verified as a bug in Real-Time Workshop 5.1 (R13SP1) and earlier in the way that Real-Time Workshop handles Simulink parameters with long character strings. There is currently not adequate protection against buffer overflows in the parameters when Real-Time Workshop writes out the ".rtw" file.

Currently, to work around this issue, try using the parameter type "string" instead.