rasmol fails to build on BigSur

[richard-evans (Dr. Richard Evans)]

Hi rasmol fails to build on M1/bigsur with the following error:

MOLDIR=\"/opt/local/share/rasmol/\" -DTHIRTYTWOBIT -D_USE_RASMOL_H_ -c -o repres.o repres.c :info:build clang: clang: clang: clangclang: : error: no such file or directory: 'DarwinMachineDefines'

It seems like an old definition that was recently removed in macOS, but I can't find any reference to it in the source code and google is unhelpful. Removing the definition "DarwinMachineDefines" in the makefile seems to fix it (it installs OK after that and runs fine) but not sure the best way to patch the port (bit of a port newbie) and whether removing this is in general safe.

Any thoughts?

Many thanks,

Richard