If DEFAULT_SYSROOT is not specfied when building flang, then the -isysroot flag is needed to link binaries against system libraries on Darwin. It's also needed when linking against a non-default sysroot.
If DEFAULT_SYSROOT is not specfied when building flang, then the -isysroot flag is needed to link binaries against system libraries on Darwin. It's also needed when linking against a non-default sysroot.