diff options
| -rw-r--r-- | doc/changelog/04-tactics/12116-master+fix12045-missing-reduction-in-using-ind-scheme.rst | 5 | ||||
| -rw-r--r-- | tactics/tactics.ml | 2 | ||||
| -rw-r--r-- | test-suite/bugs/closed/bug_12045.v | 19 |
3 files changed, 25 insertions, 1 deletions
diff --git a/doc/changelog/04-tactics/12116-master+fix12045-missing-reduction-in-using-ind-scheme.rst b/doc/changelog/04-tactics/12116-master+fix12045-missing-reduction-in-using-ind-scheme.rst new file mode 100644 index 0000000000..7af2b4d97b --- /dev/null +++ b/doc/changelog/04-tactics/12116-master+fix12045-missing-reduction-in-using-ind-scheme.rst @@ -0,0 +1,5 @@ +- **Fixed:** + Anomaly with induction schemes whose conclusion is not normalized + (`#12116 <https://github.com/coq/coq/pull/12116>`_, + by Hugo Herbelin; fixes + `#12045 <https://github.com/coq/coq/pull/12045>`_) diff --git a/tactics/tactics.ml b/tactics/tactics.ml index c79aca3d3c..8c4400a80f 100644 --- a/tactics/tactics.ml +++ b/tactics/tactics.ml @@ -4499,7 +4499,7 @@ let check_expected_type env sigma (elimc,bl) elimt = if n == 0 then error "Scheme cannot be applied."; let sigma,cl = make_evar_clause env sigma ~len:(n - 1) elimt in let sigma = solve_evar_clause env sigma true cl bl in - let (_,u,_) = destProd sigma cl.cl_concl in + let (_,u,_) = destProd sigma (whd_all env sigma cl.cl_concl) in fun t -> match Evarconv.unify_leq_delay env sigma t u with | _sigma -> true | exception Evarconv.UnableToUnify _ -> false diff --git a/test-suite/bugs/closed/bug_12045.v b/test-suite/bugs/closed/bug_12045.v new file mode 100644 index 0000000000..4e416778a9 --- /dev/null +++ b/test-suite/bugs/closed/bug_12045.v @@ -0,0 +1,19 @@ +(* Check enough reduction happens in the conclusion of an induction scheme *) + +Lemma foo : + forall (P : nat -> Prop), + (forall n, P (S n)) -> + forall n, + (fun e => + IsSucc e -> + P e) n. +Proof. +Admitted. + +Theorem bar : forall n, + IsSucc n -> + True. +Proof. + intros. + Fail induction n using foo. (* was an anomaly *) +Admitted. |