For all versions of Samba 4.7 under RedHat 7.x, if the --enable_vxfs option is enabled, a number of compiler errors occur in the file source3/modules/vfs_vxfs.h. These errors are related to the various string comparison functions. The workaround is to add "#define _SAFE_STRING_H" before the '#include "includes.h"' directive.
vxfs is support was removed