Fix a de Bruijn bug in checking code of projections.

2 files changed, 2 insertions, 2 deletions

diff --git a/kernel/term_typing.ml b/kernel/term_typing.ml
index d6df6366c..ec9541189 100644
--- a/kernel/term_typing.ml
+++ b/kernel/term_typing.ml
@@ -138,7 +138,7 @@ let check_projection env kn inst body =
       not (isLambda p)
     then cannot_recognize ()
   in
-  let (na, t, ty) = destLambda p in 
+  let (na, t, ty) = destLambda (Vars.subst1 mkProp p) in 
   let argctx, p = decompose_lam_assum b.(0) in
   (* No need to check the lambdas as the case is well-formed *)
   let () = if not (isRel p) then cannot_recognize () in
diff --git a/test-suite/bugs/opened/HoTT_coq_078.v b/test-suite/bugs/opened/HoTT_coq_078.v
index a2c97d067..6c02cad56 100644
--- a/test-suite/bugs/opened/HoTT_coq_078.v
+++ b/test-suite/bugs/opened/HoTT_coq_078.v
@@ -35,7 +35,7 @@ Definition transport_prod' {A : Type} {P Q : A -> Type} {a a' : A} (p : a = a')
        | idpath => idpath
      end. (* success *)
 
-Fail Definition transport_prod {A : Type} {P Q : A -> Type} {a a' : A} (p : a = a')
+Definition transport_prod {A : Type} {P Q : A -> Type} {a a' : A} (p : a = a')
   (z : P a * Q a)
   : transport (fun a => P a * Q a) p z  =  (transport _ p (fst z), transport _ p (snd z))
   := match p with