[Bug target/90379] Gcc 9.1 fails "make check" on linux due to missing MacOS-specific header file

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90379

--- Comment #5 from Jürgen Reuter <juergen.reuter at desy dot de> ---
I am seeing the same issue on Darwin 18.5.0 (macOSX 10.4.4) with XCode 10.2.