Index: pyo3/Cargo.toml
===================================================================
--- pyo3.orig/Cargo.toml
+++ pyo3/Cargo.toml
@@ -402,7 +402,7 @@ version = "0.4"
 optional = true
 
 [dependencies.memoffset]
-version = "0.9"
+version = ">= 0.6, < 1.0"
 
 [dependencies.num-bigint]
 version = "0.4.2"
