diff --git a/pika-build-config/lto.sh b/pika-build-config/lto.sh
index 540015b05..5c5174c27 100644
--- a/pika-build-config/lto.sh
+++ b/pika-build-config/lto.sh
@@ -1,5 +1,5 @@
-export PIKA_PACKAGE_VERSION="4.20.0-1"
-export PIKA_PACKAGE_NAME="libtasn1-6"
+export PIKA_PACKAGE_VERSION="1:20.1.0~+rc1-1~exp1"
+export PIKA_PACKAGE_NAME="llvm-toolchain-20"
 export PIKA_PACKAGE_PATCH=false
 export PIKA_REBUILD=false
 export PIKA_REBUILD_VERSION="b0"