diff --git a/llvm/docs/CMake.rst b/llvm/docs/CMake.rst
--- a/llvm/docs/CMake.rst
+++ b/llvm/docs/CMake.rst
@@ -489,6 +489,11 @@
 **LLVM_ENABLE_EXPENSIVE_CHECKS**:BOOL
   Enable additional time/memory expensive checking. Defaults to OFF.
 
+**LLVM_ENABLE_HTTPLIB**:BOOL
+  Enables the optional cpp-httplib dependency which is used by llvm-debuginfod
+  to serve debug info over HTTP. `cpp-httplib <https://github.com/yhirose/cpp-httplib>`_
+  must be installed, or `httplib_ROOT` must be set. Defaults to OFF.
+
 **LLVM_ENABLE_FFI**:BOOL
   Indicates whether the LLVM Interpreter will be linked with the Foreign Function
   Interface library (libffi) in order to enable calling external functions.