diff --git a/CMakeLists.txt b/CMakeLists.txt
index d2d5d1337..3db4123c5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -6,7 +6,7 @@
 # See http://swift.org/LICENSE.txt for license information
 # See http://swift.org/CONTRIBUTORS.txt for Swift project authors
 
-cmake_minimum_required(VERSION 3.17)
+cmake_minimum_required(VERSION 3.15.1)
 
 list(APPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake/modules)