diff --git a/coq-lambda-rust.opam b/coq-lambda-rust.opam
index 135f16ead52fcc276265c68acc66824d4e08c02d..29cff8106c3d0b3ee8fdd31a44f4042ca68d3b94 100644
--- a/coq-lambda-rust.opam
+++ b/coq-lambda-rust.opam
@@ -13,7 +13,7 @@ the type system, and safety proof for some Rust libraries.
 """
 
 depends: [
-  "coq-iris" { (= "dev.2021-07-16.0.ca19ab25") | (= "dev") }
+  "coq-iris" { (= "dev.2021-07-19.2.0ae9d9ee") | (= "dev") }
 ]
 
 build: [make "-j%{jobs}%"]
diff --git a/theories/lifetime/model/creation.v b/theories/lifetime/model/creation.v
index 9aa2e3ae38c58bb817ecfa0a9caf25c4e3377855..dbfdff98dff95b716b776af3e371a2e29d9caa15 100644
--- a/theories/lifetime/model/creation.v
+++ b/theories/lifetime/model/creation.v
@@ -53,8 +53,7 @@ Proof.
   iModIntro. rewrite /lft_inv_dead. iExists Q. iFrame.
   rewrite /lft_bor_dead. iExists (dom _ B), P.
   rewrite !gset_to_gmap_dom -map_fmap_compose.
-  rewrite (map_fmap_ext _ ((1%Qp,.) ∘ to_agree) B); last first.
-  { move=>?? /HB ->. done. }
+  rewrite (map_fmap_ext _ ((1%Qp,.) ∘ to_agree) B); last naive_solver.
   iFrame.
 Qed.