Index: b/Cargo.toml
===================================================================
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -418,7 +418,7 @@
 optional = true
 
 [dependencies.memoffset]
-version = "0.9"
+version = ">= 0.6, < 1.0"
 
 [dependencies.num-bigint]
 version = "0.4.2"
