Note: this distinguishes between MEX function generation (used in MATLAB) and standalone code generation (source code, static library, dynamic library, or executable).
1. Make sure to follow the recommended workflow for generating code using MATLAB Coder. For detailed guidance, execute the following command in the MATLAB R2018b Command Window to access the release-specific documentation on Workflow for Preparing MATLAB Code for Code Generation:
web(fullfile(docroot, 'coder/ug/preparing-matlab-code-for-c-c-code-generation-workflow.html'))
In particular, make sure to generate and test a MEX function, which contains runtime error checking that may not appear in standalone code.
2. In R2015b and later, runtime error checking can be generated in standalone code using a config object for code generation:
>> cfg = coder.config('lib');
>> cfg.RuntimeChecks = 1;
>> codegen myFunction -config cfg
3. If you are seeing different results from generated code than what you see from MATLAB for the same function, check for the possibility that the generated code is simply using a different (but still correct) implementation of that function. For example, the 'svd' function can output different answers from MATLAB vs generated C code. Note that singular value decomposition is not unique, so a matrix can have multiple decompositions that are all valid. To learn more, run the following command in the MATLAB R2019b command window:
>> web(fullfile(docroot, 'matlab/ref/double.svd.html'))
4. Check that the compiler is supported, as per the following page:
5. Check if there were any warnings during code generation.
6. If generated, ensure that the initialization function is called before the entry-point function, and that the terminate function is called after. Re-entrant code generation requires manually calling the initialize function prior to invoking the entry-point functions. For more information, run the following command in the MATLAB R2018b command window:
web(fullfile(docroot, 'coder/ug/calling-generated-c-c-functions.html'))
7. Check any calls to external C functions via coder.ceval, ensuring the data type and layout are correct (note that MATLAB uses a column-major layout by default).
8. Try compiling with the debug flag. For MEX, add -g to the codegen command:
>> codegen myFunction -args {1,2} -g
For standalone code generation, create a coder.config object and modify it:
>> cfg = coder.config('dll');
>> cfg.BuildConfiguration = 'Debug';
>> codegen myFunction -config cfg
If (8) resolves the issue, please contact MathWorks Technical Support to report this compiler bug.
If none of the above resolve the issue, please contact MathWorks Technical Support.
Please follow the link below to search for the required information regarding the current release:
