diff --git a/polly/lib/External/CMakeLists.txt b/polly/lib/External/CMakeLists.txt
index 458925f9b6e4..1869410c8baa 100644
--- a/polly/lib/External/CMakeLists.txt
+++ b/polly/lib/External/CMakeLists.txt
@@ -306,6 +306,7 @@ if (POLLY_BUNDLED_ISL)
 
   target_link_libraries(polly-isl-test PRIVATE
     PollyISL
+    LLVMSupport
     )
 
   # ISL requires at least C99 to compile. gcc < 5.0 use -std=gnu89 as default.