diff --git a/Mk/Uses/cmake.mk b/Mk/Uses/cmake.mk
--- a/Mk/Uses/cmake.mk
+++ b/Mk/Uses/cmake.mk
@@ -90,7 +90,8 @@
 			-DCMAKE_BUILD_TYPE:STRING="${CMAKE_BUILD_TYPE}" \
 			-DTHREADS_HAVE_PTHREAD_ARG:BOOL=YES \
 			-DCMAKE_INSTALL_RPATH_USE_LINK_PATH=YES \
-			-DCMAKE_VERBOSE_MAKEFILE:BOOL=ON
+			-DCMAKE_VERBOSE_MAKEFILE:BOOL=ON \
+			-DFETCHCONTENT_FULLY_DISCONNECTED:BOOL=ON
 
 # Handle the option-like CMAKE_ON and CMAKE_OFF lists.
 .  for _bool_kind in ON OFF