fix `ethbloom test` by falling back to rustc-hex
@@ -17,7 +17,7 @@ serde = { version = "1.0", optional = true }
[dev-dependencies]
rand = { version = "0.4" }
-rustc-hex = "2.0"
+rustc-hex = "1.0.0"
[features]
default = ["std", "heapsizeof", "serialize", "fixed-hash/libc"]
