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

Calculating dependencies ... done!
Dependency resolution took 1.71 s (backtrack: 5/20).

[ebuild  N     ] dev-lang/ocaml-4.14.2:0/4.14.2::gentoo  USE="ocamlopt -emacs -flambda -latex -xemacs" 5377 KiB
[ebuild  N     ] dev-libs/libpcre-8.45-r4:3::gentoo  USE="bzip2 cxx jit pcre16 readline (unicode) zlib -libedit -pcre32 -static-libs -valgrind" 1542 KiB
[ebuild  N     ] dev-ml/dune-3.23.1:0/3.23.1::gentoo  USE="-emacs -test" 3624 KiB
[ebuild  N     ] dev-ml/findlib-1.9.8::gentoo  USE="ocamlopt -doc -tk" 269 KiB
[ebuild  N     ] dev-ml/ocamlbuild-0.16.1:0/0.16.1::gentoo  USE="ocamlopt" 198 KiB
[ebuild  N     ] dev-ml/result-1.5:0/1.5::gentoo  USE="ocamlopt" 3 KiB
[ebuild  N     ] dev-ml/sexplib0-0.16.0:0/0.16.0::gentoo  USE="ocamlopt" 22 KiB
[ebuild  N     ] dev-ml/cppo-1.8.0:0/1.8.0::gentoo  USE="ocamlopt" 43 KiB
[ebuild  N     ] dev-ml/csexp-1.5.2-r1:0/1.5.2::gentoo  USE="ocamlopt -test" 12 KiB
[ebuild  N     ] dev-ml/dune-configurator-3.21.1:0/3.21.1::gentoo  USE="ocamlopt" 3352 KiB
[ebuild  N     ] dev-ml/base-0.16.3-r1:0/0.16::gentoo  USE="ocamlopt" 433 KiB
[ebuild  N     ] dev-ml/stdio-0.16.0:0/0.16::gentoo  USE="ocamlopt" 8 KiB
[ebuild  N     ] dev-ml/pcre-ocaml-7.5.0:0/7.5.0::gentoo  USE="ocamlopt -examples" 41 KiB
[ebuild  N     ] dev-ml/ocamlnet-4.1.9-r2:0/4.1.9::gentoo  USE="ocamlopt pcre ssl -httpd -kerberos -tk -zip" 4521 KiB

Total: 14 packages (14 new), Size of downloads: 19437 KiB

WARNING: One or more updates/rebuilds have been skipped due to a dependency conflict:

dev-lang/ocaml:0

  (dev-lang/ocaml-5.5.1:0/5.5.1::gentoo, ebuild scheduled for merge) USE="ocamlopt -emacs -flambda -latex -test -xemacs" conflicts with
    <dev-lang/ocaml-5:=[ocamlopt] required by (dev-ml/ocamlnet-4.1.9-r2:0/4.1.9::gentoo, ebuild scheduled for merge) USE="ocamlopt pcre ssl -httpd -kerberos -tk -zip"
    ^               ^            


!!! The following update(s) have been skipped due to unsatisfied dependencies
!!! triggered by backtracking:

dev-ml/stdio:0
dev-ml/findlib:0