diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 3bc08ed1..53d5fdff 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -105,7 +105,7 @@ jobs:
             supported: true
           - toolset: clang
             compiler: clang++-5.0
-            cxxstd: "11,14,1z"
+            cxxstd: "11,14"
             os: ubuntu-22.04
             container: ubuntu:16.04
             install: clang-5.0