diff --git a/pika-build-config/lto.sh b/pika-build-config/lto.sh
index 225c1ca5b..c8fa80dc9 100644
--- a/pika-build-config/lto.sh
+++ b/pika-build-config/lto.sh
@@ -1,5 +1,5 @@
-export PIKA_PACKAGE_VERSION="0.5+git20200117-4.1"
-export PIKA_PACKAGE_NAME="hdrmerge"
+export PIKA_PACKAGE_VERSION="4.0.0-4"
+export PIKA_PACKAGE_NAME="mpi4py"
 export PIKA_PACKAGE_PATCH=false
 export PIKA_REBUILD=false
 export PIKA_REBUILD_VERSION="b0"