diff --git a/clang/docs/ThinLTO.rst b/clang/docs/ThinLTO.rst
index e127413c002..2d5d0a71fa6 100644
--- a/clang/docs/ThinLTO.rst
+++ b/clang/docs/ThinLTO.rst
@@ -225,6 +225,10 @@ To bootstrap clang/LLVM with ThinLTO, follow these steps:
    ``CMAKE_EXE_LINKER_FLAGS:STRING=``. Note the configure may fail if
    linker plugin options are instead specified directly in the previous step.
 
+The `BOOTSTRAP_LLVM_ENABLE_LTO=Thin`` will enable ThinLTO for stage 2 and
+stage 3 in case the compiler used for stage 1 does not support the ThinLTO
+option.
+
 More Information
 ================