diff --git a/Sources/Clang/Utilities.swift b/Sources/Clang/Utilities.swift
index 389731b..141ad55 100644
--- a/Sources/Clang/Utilities.swift
+++ b/Sources/Clang/Utilities.swift
@@ -1,3 +1,5 @@
+import Foundation
+
 #if SWIFT_PACKAGE
 import cclang
 #endif