###################################### Tinker Notes for GNU gfortran on macOS ###################################### This subdirectory contains a set of script files that can be used to build the Tinker program package on a macOS system using GNU gcc/gfortran compilers under OpenMP parallelization. These scripts have been tested with compiler version 7.1. Earlier versions of the compiler, in particular those before 4.7, do not work correctly due to lack of support for some features of the OpenMP standard. Building reasonably portable executables requires linking with static gcc libraries. This can be done via use of versions of gfortran that enforce the -static-libgcc flag, or by copying the static libraries from the gcc directories into the Tinker build directory, as noted in "link.make". Alternatively, on macOS the shared versions, libquadmath.dylib and libquadmath.0.dylib, can be moved or renamed from within the directory containing the compiler libraries. If some or all of the executables fail via a segmentation fault, check the limits for your processes by issuing the "limit" command at the tcsh shell prompt (or similar under other shells). By default, these limits are set to quite small values. To eliminate the problem issue the following commands: limit datasize unlimited limit stacksize unlimited These same commands can also be put in your .tcshrc file or equivalent startup file to be run at login time.