--- CMakeLists.txt.orig	2020-03-14 17:13:03 UTC
+++ CMakeLists.txt
@@ -21,7 +21,9 @@ add_subdirectory("lib")
 add_subdirectory("share")
 add_subdirectory("dune")
 add_subdirectory("bin")
+if (FREEBSD_INSTALL_DOCS)
 add_subdirectory("doc")
+endif()
 add_subdirectory("cmake/modules")
 add_subdirectory("cmake/scripts")