gistfile1.txt

$ opam install camlp4
The following actions will be performed:
  ∗  install camlp4 4.03

=-=- Gathering sources =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=  🐫 
[camlp4] git://github.com/ocaml/camlp4#trunk already up-to-date

=-=- Processing actions -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=  🐫 
[ERROR] The compilation of camlp4 failed at "./configure --bindir=/Users/tony/.opam/system/bin
        --libdir=/Users/tony/.opam/system/lib/ocaml --pkgdir=/Users/tony/.opam/system/lib".
Processing  1/1: [camlp4: rm]
#=== ERROR while installing camlp4.4.03 =======================================#
# opam-version 1.2.2
# os           darwin
# command      ./configure --bindir=/Users/tony/.opam/system/bin --libdir=/Users/tony/.opam/system/lib/ocaml --pkgdir=/Users/tony/.opam/system/lib
# path         /Users/tony/.opam/system/build/camlp4.4.03
# compiler     system (4.04.0)
# exit-code    2
# env-file     /Users/tony/.opam/system/build/camlp4.4.03/camlp4-75251-6d07ae.env
# stdout-file  /Users/tony/.opam/system/build/camlp4.4.03/camlp4-75251-6d07ae.out
# stderr-file  /Users/tony/.opam/system/build/camlp4.4.03/camlp4-75251-6d07ae.err
### stdout ###
# This version of Camlp4 is for OCaml 4.06 but you are using OCaml 4.04.0.
# If building Camlp4 directly from git, use the 4.04 branch.



=-=- Error report -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=  🐫 
The following actions failed
  ∗  install camlp4 4.03
No changes have been performed