diff --git a/pika-build-config/lto.sh b/pika-build-config/lto.sh
index 44a62890e..0348162b0 100644
--- a/pika-build-config/lto.sh
+++ b/pika-build-config/lto.sh
@@ -1,5 +1,5 @@
-export PIKA_PACKAGE_VERSION="0.49+dfsg-1"
-export PIKA_PACKAGE_NAME="r-cran-xfun"
+export PIKA_PACKAGE_VERSION="2:1.8.10-2"
+export PIKA_PACKAGE_NAME="libx11"
 export PIKA_PACKAGE_PATCH=false
 export PIKA_REBUILD=false
 export PIKA_REBUILD_VERSION="b0"