diff --git a/pika-build-config/lto.sh b/pika-build-config/lto.sh
index 9b71cb3c9..5931b6ecd 100644
--- a/pika-build-config/lto.sh
+++ b/pika-build-config/lto.sh
@@ -1,5 +1,5 @@
-export PIKA_PACKAGE_VERSION="0.5.3-1"
-export PIKA_PACKAGE_NAME="r-cran-splines2"
+export PIKA_PACKAGE_VERSION="4.2-1"
+export PIKA_PACKAGE_NAME="haskell-copilot-theorem"
 export PIKA_PACKAGE_PATCH=false
 export PIKA_REBUILD=false
 export PIKA_REBUILD_VERSION="b0"