Bug report: NDIV=1 in SubDyn produces FATAL ERROR

[lapadron]

Bug description
Setting NDIV=1 in SubDyn produces FATAL ERROR with the following problem:

FAST_InitializeAll:SD_Init:EigenSolve:LAPACK_DGGEV: The QZ iteration failed. No eigenvectors have
been calculated.

FAST encountered an error during module initialization.
Simulation error level: FATAL ERROR

Hints to solve the problem are welcome.

To Reproduce

1. Compile with Intel Fortran Compiler or gfortran, in linux
2. Run 5MW_OC3Mnpl_DLL_WTurb_WavesIrr case with NDIV=1 in Subdyn datafile. The problem ocurrs at init, so it is independent of most other parameters.
3. See the error

Expected behavior
The code is apparently prepared for NDIV=1, but it doesn't work. Initially, it seems that K matrix is not correctly written.

OpenFAST Version
OpenFAST-v2.2.0-10-g6d9e2b9f-dirty
Compile Info:

• Architecture: 64 bit
• Precision: double
• Date: Mar 05 2020
• Time: 15:44:33
  Execution Info:
• Date: 03/20/2020
• Time: 14:31:39-0000

System Information (please complete the following information):

• OS: Ubuntu 18.04
• Compiler: ifort + MKL version 19.0.4.243 (with gfortran, it also breaks, but gives no information)
• Compiler settings: Default

Complete output
OpenFAST input file heading:
FAST Certification Test #19: NREL 5.0 MW Baseline Wind Turbine with OC3 Monopile RF
Configuration, for use in offshore analysis

Running ElastoDyn.
Running AeroDyn.
Running BEM.
Running UnsteadyAero.
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 1, Blade = 1
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 2, Blade = 1
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 3, Blade = 1
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 4, Blade = 1
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 1, Blade = 2
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 2, Blade = 2
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 3, Blade = 2
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 4, Blade = 2
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 1, Blade = 3
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 2, Blade = 3
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 3, Blade = 3
Warning: Turning off Unsteady Aerodynamics because C_nalpha is 0. BladeNode = 4, Blade = 3
Running InflowWind.

Reading a 31x31 grid (145 m wide, 17.5 m to 162.5 m above ground) with a characteristic wind
speed of 12 m/s. This full-field file was generated by TurbSim (v1.06.00, 21-Sep-2012) on
07-Jan-2014 at 12:50:45.

Processed 1442 time steps of 20-Hz full-field data (72.05 seconds).

Running ServoDyn.
Running ServoDyn Interface for Bladed Controllers.
Running HydroDyn.
Generating incident wave kinematics and current time history.
Calculating second order difference frequency wave kinematics.
Calculating second order sum frequency wave kinematics.
Running SubDyn.

FAST_InitializeAll:SD_Init:EigenSolve:LAPACK_DGGEV: The QZ iteration failed. No eigenvectors have
been calculated.

FAST encountered an error during module initialization.
Simulation error level: FATAL ERROR

Aborting OpenFAST.

[lapadron]

I found out that it is already fixed in dev branch. Line 399 SD_FEM.