diff --git a/.travis.yml b/.travis.yml
index 0053553..cdeaea2 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -339,7 +339,7 @@ matrix:
     - os: linux
       dist: bionic
       compiler: clang++-libc++
-      env: UBSAN=1 TOOLSET=clang COMPILER=clang++-libc++ CXXSTD=03,11,14,1z UBSAN_OPTIONS=print_stacktrace=1
+      env: UBSAN=1 TOOLSET=clang COMPILER=clang++-libc++ CXXSTD=03,11,14,17,2a UBSAN_OPTIONS=print_stacktrace=1
       addons:
         apt:
           packages: