These are the packages that would be merged, in order:

Calculating dependencies ... done!
Dependency resolution took 0.98 s (backtrack: 0/20).

[ebuild  N     ] dev-lang/ocaml-5.5.1:0/5.5.1::gentoo  USE="ocamlopt -emacs -flambda -latex -test -xemacs" 6457 KiB
[ebuild  N     ] dev-ml/dune-3.18.1:0/3.18.1::gentoo  USE="-emacs" 2851 KiB

Total: 2 packages (2 new), Size of downloads: 9307 KiB