Merge branch 'v8.6' into trunk

1 files changed, 3 insertions, 2 deletions

diff --git a/kernel/nativecode.ml b/kernel/nativecode.ml
index 33bd7d8dd..d9659d681 100644
--- a/kernel/nativecode.ml
+++ b/kernel/nativecode.ml
@@ -1848,9 +1848,10 @@ and apply_fv env sigma univ (fv_named,fv_rel) auxdefs ml =
   auxdefs, MLlet(aux_name, ml, mkMLapp (MLlocal aux_name) (Array.of_list (fv_rel@fv_named)))
 
 and compile_rel env sigma univ auxdefs n =
-  let n = Context.Rel.length env.env_rel_context - n in
   let open Context.Rel.Declaration in
-  match Context.Rel.lookup n env.env_rel_context with
+  let decl = Context.Rel.lookup n env.env_rel_context in
+  let n = Context.Rel.length env.env_rel_context - n in
+  match decl with
   | LocalDef (_,t,_) ->
       let code = lambda_of_constr env sigma t in
       let auxdefs,code = compile_with_fv env sigma univ auxdefs None code in