diff options
Diffstat (limited to 'kernel/mod_typing.ml')
| -rw-r--r-- | kernel/mod_typing.ml | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/kernel/mod_typing.ml b/kernel/mod_typing.ml index 7417b42619..8fee8481d7 100644 --- a/kernel/mod_typing.ml +++ b/kernel/mod_typing.ml @@ -108,7 +108,15 @@ and merge_with env mtb with_decl = | _ -> error_not_a_module (string_of_label l) in let mtb = type_modpath env' mp in - (* here, we should assert that there is no msid in mtb *) + (* here, using assertions in substitutions, + we check that there is no msid bound in mtb *) + begin + try + let _ = subst_modtype (map_msid msid (MPself msid)) mtb in + () + with + Assert_failure _ -> error_circular_with_module id + end; let cst = check_subtypes env' mtb old.msb_modtype in let equiv = match old.msb_equiv with |