On macOS, when DMD invokes the C preprocessor, it does so improperly when the -os command-line switch is set to anything other than host or osx.
When cross-compiling, the preprocessor is invoked as though it were GCC instead of clang (which is what it is expected to be when running on macOS).
This results in clang attempting to compile and link the file that was submitted for preprocessing.
On macOS, when DMD invokes the C preprocessor, it does so improperly when the
-oscommand-line switch is set to anything other thanhostorosx.When cross-compiling, the preprocessor is invoked as though it were GCC instead of clang (which is what it is expected to be when running on macOS).
This results in clang attempting to compile and link the file that was submitted for preprocessing.