Refactor CPP surrounding unwind declarations in StgCRun
This code reportedly breaks on Clang platforms (like Darwin, #15207 (closed)). Only enable it on Linux for now and refactor the CPP to be more suggestive of its intent.
This code reportedly breaks on Clang platforms (like Darwin, #15207 (closed)). Only enable it on Linux for now and refactor the CPP to be more suggestive of its intent.