Added in https://github.com/llvm/llvm-project/pull/137515, as the source uses unistd.h which isn't present there. | C:\Users\tcwg\llvm-worker\lldb-aarch64-windows\llvm-project\lldb\test\Shell\Commands/Inputs/sigchld.c:4:10: fatal error: 'unistd.h' file not found | 4 | #include <unistd.h> | | ^~~~~~~~~~ | 1 error generated.