diff --git a/library/CMakeLists.txt b/library/CMakeLists.txt
index 19ba315..bef0dbf 100644
--- a/library/CMakeLists.txt
+++ b/library/CMakeLists.txt
@@ -19,6 +19,7 @@
     base64.c
     bignum.c
     bignum_new.c
+    bignum_core.c
     camellia.c
     ccm.c
     chacha20.c