Use clang 19

Signed-off-by: Stefan Marr <git@stefan-marr.de>

Author: smarr

.gitlab-ci.yml

@@ -51,7 +51,7 @@ build_and_test:
   tags: [$MACHINE]
   script:
     - if [ "$COMPILER" = "gcc" ];   then export CC=gcc-13;   export CXX=g++-13; fi
-    - if [ "$COMPILER" = "clang" ]; then export CC=clang$MP-18; export CXX=clang++$MP-18; fi
+    - if [ "$COMPILER" = "clang" ]; then export CC=clang$MP-19; export CXX=clang++$MP-19; fi
 
     # compose a name for this configuration
     - |+