diff --git a/environments/hlrs/spack.yaml b/environments/hlrs/spack.yaml
index 05976b5..7e1682d 100644
--- a/environments/hlrs/spack.yaml
+++ b/environments/hlrs/spack.yaml
@@ -13,6 +13,12 @@ spack:
     - matrix:    # modules for low-level tools
       - [libunwind, papi]
       - [$%core_compiler]
+    - matrix:
+      - [otf-cpt]
+      - [$^mpis]
+      - [$%compilers]
+      exclude:
+        - otf-cpt%gcc  # gcc's OpenMP runtime does not support OMPT
     - matrix:
       - [mpip, extrae]
       - [$cflags_noerror_implicit]    # code is not fully C99