diff --git a/libunwind/CMakeLists.txt b/libunwind/CMakeLists.txt
index 69d17a46c57d..3ba4b65d175a 100644
--- a/libunwind/CMakeLists.txt
+++ b/libunwind/CMakeLists.txt
@@ -49,7 +49,8 @@ if (CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
     execute_process(
       COMMAND ${LLVM_CONFIG_PATH} --cmakedir
       RESULT_VARIABLE HAD_ERROR
-      OUTPUT_VARIABLE CONFIG_OUTPUT)
+      OUTPUT_VARIABLE CONFIG_OUTPUT
+      ERROR_QUIET)
     if(NOT HAD_ERROR)
       string(STRIP "${CONFIG_OUTPUT}" LLVM_CMAKE_PATH)
     else()