diff --git a/libunwind/docs/CMakeLists.txt b/libunwind/docs/CMakeLists.txt
--- a/libunwind/docs/CMakeLists.txt
+++ b/libunwind/docs/CMakeLists.txt
@@ -1,5 +1,5 @@
 include(FindSphinx)
-if (SPHINX_FOUND)
+if (SPHINX_FOUND AND LLVM_ENABLE_SPHINX)
   include(AddSphinxTarget)
   if (${SPHINX_OUTPUT_HTML})
     add_sphinx_target(html libunwind)