message: Avoid using header from Host/macosx when not testing an apple build.
diff: //===----------------------------------------------------------------------===//
  #include "lldb/Host/HostInfo.h"
  -#include "lldb/Host/macosx/HostInfoMacOSX.h"
  #include "lldb/lldb-defines.h"
  #include "TestingSupport/TestUtilities.h"
  #include "gtest/gtest.h"
  +#ifdef __APPLE__
  +#include "lldb/Host/macosx/HostInfoMacOSX.h"
  +#endif
  +
  using namespace lldb_private;
  using namespace llvm;
  @@ -47,6 +50,8 @@ TEST_F(HostInfoTest, GetAugmentedArchSpec) {
  }
  +#ifdef __APPLE__
  +
  struct HostInfoMacOSXTest : public HostInfoMacOSX {
  static std::string ComputeClangDir(std::string lldb_shlib_path,
  bool verify = false) {
  @@ -58,7 +63,6 @@ struct HostInfoMacOSXTest : public HostInfoMacOSX {
  };
  -#ifdef __APPLE__
  TEST_F(HostInfoTest, MacOSX) {
  // This returns whatever the POSIX fallback returns.
  std::string posix = "/usr/lib/liblldb.dylib";
  