diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 781368840c5f1241306f9f9e489f97ef59ddff1a..9e7235709ad61f595cb3c191873075b31edd893b 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -173,6 +173,7 @@ build-documentation:
   script:
     - export PYTHONPATH=`pwd`
     - mkdir html_doc
+    - sphinx-build -b html doc  html_doc
     - sphinx-build -W -b html doc  html_doc
   tags:
     - docker