Error when appending paths from boost::filesystem

NOTE: This issue references the CoE system Tulip, do not include any discussion of material covered by the NDA.

When I run the test suite on Tulip I get a bunch of exceptions when appending to test::getTestDirectory(). The problem is reminiscent of what is seen in this SO post (https://stackoverflow.com/questions/56738708/c-stdbad-alloc-on-stdfilesystempath-append), although that's for std::filesystem.

For example, this fails:

mm::fs::path inputPath = test::getTestDirectory() / "input" / "test_input_meumapps-ss_2.json";

So does this:

std::string a("input");
std::string b("test_input_meumapps-ss_2.json");
mm::fs::path inputPath = test::getTestDirectory() / a / b;

However, this doesn't fail:

std::string pathString = test::getTestDirectory().native() + "/input/test_input_meumapps-ss_2.json";
mm::fs::path inputPath = pathString;

I'm still tracking down exactly what could cause this.