From 37a58edffeff7b6a7f03ec781e1e2ca73de4b3af Mon Sep 17 00:00:00 2001
From: Matthieu Sozeau
Date: Thu, 14 Aug 2014 13:01:30 +0200
Subject: Restrict eta-conversion to inductive records, fixing bug #3310.

---
 kernel/closure.ml             |  3 ++-
 pretyping/evarconv.ml         | 22 +++++++++++-----------
 test-suite/bugs/closed/3310.v | 10 ++++++++++
 test-suite/bugs/closed/3482.v | 11 +++++++++++
 test-suite/bugs/opened/3310.v | 10 ----------
 5 files changed, 34 insertions(+), 22 deletions(-)
 create mode 100644 test-suite/bugs/closed/3310.v
 create mode 100644 test-suite/bugs/closed/3482.v
 delete mode 100644 test-suite/bugs/opened/3310.v

diff --git a/kernel/closure.ml b/kernel/closure.ml
index 62ee5db5d5..6dacb7818c 100644
--- a/kernel/closure.ml
+++ b/kernel/closure.ml
@@ -866,7 +866,8 @@ let rec get_parameters depth n argstk =
 let eta_expand_ind_stacks env ind m s (f, s') =
   let mib = lookup_mind (fst ind) env in
     match mib.Declarations.mind_record with
-    | Some (exp,projs) when Array.length projs > 0 -> 
+    | Some (exp,projs) when Array.length projs > 0 
+      && mib.Declarations.mind_finite -> 
       let primitive = Environ.is_projection projs.(0) env in
 	if primitive then
 	  (* (Construct, pars1 .. parsm :: arg1...argn :: []) ~= (f, s') ->
diff --git a/pretyping/evarconv.ml b/pretyping/evarconv.ml
index ed04c71503..68dfb1a1bd 100644
--- a/pretyping/evarconv.ml
+++ b/pretyping/evarconv.ml
@@ -745,21 +745,21 @@ and conv_record trs env evd (ctx,(h,h'),c,bs,(params,params1),(us,us2),(ts,ts1),
 and eta_constructor ts env evd sk1 ((ind, i), u) sk2 term2 =
   let mib = lookup_mind (fst ind) env in
     match mib.Declarations.mind_record with
-    | Some (exp,projs) when Array.length projs > 0 -> 
+    | Some (exp,projs) when Array.length projs > 0
+      && mib.Declarations.mind_finite -> 
       let pars = mib.Declarations.mind_nparams in
 	(try 
 	   let l1' = Stack.tail pars sk1 in
-	     if Environ.is_projection projs.(0) env then
-	       let l2' = 
-		 let term = Stack.zip (term2,sk2) in 
-		   List.map (fun p -> mkProj (p, term)) (Array.to_list projs)
-	       in
-		 exact_ise_stack2 env evd (evar_conv_x ts) l1' 
-		   (Stack.append_app_list l2' Stack.empty)
-	     else raise (Failure "")
+	   let l2' = 
+	     let term = Stack.zip (term2,sk2) in 
+	       List.map (fun p -> mkProj (p, term)) (Array.to_list projs)
+	   in
+	     exact_ise_stack2 env evd (evar_conv_x ts) l1' 
+	       (Stack.append_app_list l2' Stack.empty)
 	 with 
-	 | Invalid_argument _ (* Stack.tail: partially applied constructor *)
-	 | Failure _ -> UnifFailure(evd,NotSameHead))
+	 | Invalid_argument _ ->
+	   (* Stack.tail: partially applied constructor *)
+	   UnifFailure(evd,NotSameHead))
     | _ -> UnifFailure (evd,NotSameHead)
 
 (* Profiling *)
diff --git a/test-suite/bugs/closed/3310.v b/test-suite/bugs/closed/3310.v
new file mode 100644
index 0000000000..ee9f8edfd3
--- /dev/null
+++ b/test-suite/bugs/closed/3310.v
@@ -0,0 +1,10 @@
+Set Primitive Projections.
+
+CoInductive stream A := cons { hd : A; tl : stream A }.
+
+CoFixpoint id {A} (s : stream A) := cons _ (hd s) (id (tl s)).
+
+Lemma id_spec : forall A (s : stream A), id s = s.
+Proof.
+intros A s.
+Fail Timeout 1 change (id s) with (cons _ (hd (id s)) (tl (id s))).
diff --git a/test-suite/bugs/closed/3482.v b/test-suite/bugs/closed/3482.v
new file mode 100644
index 0000000000..34a5e73da7
--- /dev/null
+++ b/test-suite/bugs/closed/3482.v
@@ -0,0 +1,11 @@
+Set Primitive Projections.
+Class Foo (F : False) := { foo : True }.
+Arguments foo F {Foo}.
+Print Implicit foo. (* foo : forall F : False, Foo F -> True
+
+Argument Foo is implicit and maximally inserted *)
+Check foo _. (* Toplevel input, characters 6-11:
+Error: Illegal application (Non-functional construction):
+The expression "foo" of type "True"
+cannot be applied to the term
+ "?36" : "?35" *)
\ No newline at end of file
diff --git a/test-suite/bugs/opened/3310.v b/test-suite/bugs/opened/3310.v
deleted file mode 100644
index ee9f8edfd3..0000000000
--- a/test-suite/bugs/opened/3310.v
+++ /dev/null
@@ -1,10 +0,0 @@
-Set Primitive Projections.
-
-CoInductive stream A := cons { hd : A; tl : stream A }.
-
-CoFixpoint id {A} (s : stream A) := cons _ (hd s) (id (tl s)).
-
-Lemma id_spec : forall A (s : stream A), id s = s.
-Proof.
-intros A s.
-Fail Timeout 1 change (id s) with (cons _ (hd (id s)) (tl (id s))).
-- 
cgit v1.2.3