diff --git a/coq-lambda-rust.opam b/coq-lambda-rust.opam
index a941354d1ef44cb8e45532a60c4133b615d15c2c..c3058cebcf7d7fc3a77b7c4790a978011ca184eb 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.2021-06-17.0.adac669b") | (= "dev") }
+  "coq-iris" { (= "dev.2021-06-18.0.366d607e") | (= "dev") }
 ]
 
 build: [make "-j%{jobs}%"]
diff --git a/theories/lang/heap.v b/theories/lang/heap.v
index 62b9deff7a41ee0ffaa1b0c29b1eb2480e2209ab..306a6de47b70c3ac7ccf20f0c4184893dbf93484 100644
--- a/theories/lang/heap.v
+++ b/theories/lang/heap.v
@@ -349,7 +349,7 @@ Section heap.
     etrans; first apply (IH (l +â‚— 1)).
     { intros. by rewrite shift_loc_assoc. }
     rewrite shift_loc_0 -insert_singleton_op; last first.
-    { rewrite -equiv_None big_opL_commute equiv_None big_opL_None=> l' v' ?.
+    { rewrite -None_equiv_eq big_opL_commute None_equiv_eq big_opL_None=> l' v' ?.
       rewrite lookup_singleton_None -{2}(shift_loc_0 l). apply not_inj; lia. }
     rewrite to_heap_insert. setoid_rewrite shift_loc_assoc.
     apply alloc_local_update; last done. apply lookup_to_heap_None.