Running built S-function FAST_SFunc gives undefined symbols error

[reos-rcrozier]

Bug description

In a build from the 3.5.0 branch or the 'main' branch, the Matlab S-function FAST_SFunc is built, but attempting to run the function in a simulation results in the following error:

Invalid MEX-file '/home/rcrozier/src/openfast-reos-git/build/glue-codes/simulink/FAST_SFunc.mexa64':
        /home/rcrozier/src/openfast-reos-git/build/glue-codes/simulink/FAST_SFunc.mexa64: undefined symbol:
        __polynomialroots_MOD_quarticroots

To Reproduce

Steps to reproduce the behavior:

1. Compile with

cmake ~/src/openfast-official-git \
  -DBUILD_FASTFARM=ON \
  -DBUILD_OPENFAST_CPP_API=ON \
  -DBUILD_OPENFAST_SIMULINK_API=ON \
  -DBUILD_SHARED_LIBS=OFF \
  -DCMAKE_INSTALL_PREFIX=/usr/local \
  -DDOUBLE_PRECISION=ON \
  -DOPENMP=OFF -DUSE_LOCAL_STATIC_LAPACK=OFF
make

4. Add mex function to the matlab path
5. Run OpenLoop example provided in glue-codes/simulink/examples/Run_OpenLoop.m
6. See the error

Expected behavior
Simulation runs without error.

OpenFAST Version
I built from both the main brance and the 3.5.0 branch with the same result. I also added a test for this to the github CI with the following PR: #1703

[reos-rcrozier]

With PR #1703 on the dev branch the CI test yields a slightly different undefined symbol error __seastate_types_MOD_seast_destroyparam:

  ================================================================================
  Error occurred in test_openfast_simulink/testOpenLoopRuns and it did not run to completion.
      ---------
      Error ID:
      ---------
      'Simulink:SFunctions:MexSFcnSizesInitErr'
      --------------
      Error Details:
      --------------
      Error using test_openfast_simulink/testOpenLoopRuns
      Error while obtaining sizes from MEX S-function 'FAST_SFunc' in
      'OpenLoop/FAST
      Nonlinear Wind Turbine/S-Function'.
      
      Caused by:
          Error using test_openfast_simulink/testOpenLoopRuns
          Invalid MEX-file
          '/home/runner/work/openfast/openfast/build/glue-codes/simulink/FAST_SFunc.mexa64':
      
          /home/runner/work/openfast/openfast/build/glue-codes/simulink/FAST_SFunc.mexa64:
              undefined symbol: __seastate_types_MOD_seast_destroyparam
  ================================================================================

[reos-rcrozier]

I resolved the __seastate_types_MOD_seast_destroyparam in PR #1703 but the original error remains.

[andrew-platt]

Is this still an issue?

[reos-rcrozier]

No, this no longer appears to be an issue in recent versions since the mex file is built using cmake.