OM4_05 crashes in debug mode

[nikizadehgfdl]

1/2 degree ocean-ice baseline experiment (OM4_05) crashes in debug mode (-O0) with the following traceback:

forrtl: error (182): floating invalid - possible uninitialized real/complex variable.
Image              PC                Routine            Line        Source             
fms_MOM6_SIS2_com  00000000026104D7  mom_wave_speed_mp         416  MOM_wave_speed.F90
fms_MOM6_SIS2_com  000000000116D083  mom_lateral_mixin         162  MOM_lateral_mixing_coeffs.F90
fms_MOM6_SIS2_com  0000000001093492  mom_mp_step_mom_          527  MOM.F90
fms_MOM6_SIS2_com  0000000001068C54  ocean_model_mod_m         581  ocean_model_MOM.F90
fms_MOM6_SIS2_com  000000000040F17F  MAIN__                   1020  coupler_main.F90

[Hallberg-NOAA]

This issue was addressed by https://github.com/NOAA-GFDL/MOM6/pull/1026 on November 12, 2019, and subsequent testing reveals that this test case does not crash in debug mode.