masterUncollated with #include inside decomposeParDict hangs

Summary

#include a file in the decomposeParDict. Now any parallel run will hang when run with -fileHandler masterUncollated.

See https://exchange.openfoam.com/node/1828

Steps to reproduce

Any case. See above.

What is the current bug behaviour?

Hangs. Stuck in some gatherList when parsing the dictionary (on the master).

Environment information

• OpenFOAM version : v2112

Possible fixes

decomposeParDict is special - it gets read during startup to read any roots and the number of processors. At this point the dictionary reading is not yet 'set up' so it should disable any parallel communication. The #include statement in the decomposeParDict triggers parallel communication.