check opam switch in makefile

Author: ylecornec

Makefile

@@ -69,7 +69,12 @@ ocaml_version:
 ocaml_word_size:
 	@if ! ocamlopt -config | grep "word_size:" | grep $(WORD_SIZE); then echo "invalid machine word size, expected $(WORD_SIZE)" ; exit 1; fi
 
-ocaml_checks: ocaml_version ocaml_word_size
+check_opam_switch:
+ifneq ($(DISABLE_CHECK_OPAM_SWITCH), true)
+	check_opam_switch opam.export
+endif
+
+ocaml_checks: ocaml_version ocaml_word_size check_opam_switch
 
 libp2p_helper:
 	make -C src/app/libp2p_helper

nix/ocaml.nix

@@ -133,6 +133,7 @@ let
         GO_CAPNP_STD = "${pkgs.go-capnproto2.src}/std";
 
         MARLIN_PLONK_STUBS = "${pkgs.marlin_plonk_bindings_stubs}/lib";
+        DISABLE_CHECK_OPAM_SWITCH = "true";
         configurePhase = ''
           export MINA_ROOT="$PWD"
           patchShebangs .