mdrun segfaults with group scheme .tpr
Due to a small glitch, commit ce17e81d93d7416c0e2d "Initial deactivation of group scheme" does not give a fatal error with group scheme .tpr files, but segfaults. The problem is in line 1631 of forcerec.cpp (init_forcerec): the condition "if (fr->cutoff_scheme ecutsGROUP)" can never be true at this point: ecutsGROUP is the second entry in the list of cutoff schemes and will thus be 1. Since fr has just been build using new t_forcerec before entering init_forcerec, its contents will be zero, including fr->cutoff_scheme.
A solution would be to use the condition "if (ir->cutoff_scheme ecutsGROUP)" instead.
A maybe better solution would be to move checking for the group scheme directly after .tpr file reading to runner.cpp:682.