From e93fb94e7ad61b497e66227c74ea39a228ec2241 Mon Sep 17 00:00:00 2001
From: Matt Garnett <14004106+c-o-l-o-r@users.noreply.github.com>
Date: Tue, 25 Jun 2019 10:12:49 -0400
Subject: [PATCH] calculate MAX_LENGTH_VALUE for 32-bit and 64-bit targets

---
 eth2/utils/ssz/src/lib.rs | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/eth2/utils/ssz/src/lib.rs b/eth2/utils/ssz/src/lib.rs
index 51bafa95ef..51dd16523a 100644
--- a/eth2/utils/ssz/src/lib.rs
+++ b/eth2/utils/ssz/src/lib.rs
@@ -46,9 +46,10 @@ pub use encode::{Encode, SszEncoder};
 /// The number of bytes used to represent an offset.
 pub const BYTES_PER_LENGTH_OFFSET: usize = 4;
 /// The maximum value that can be represented using `BYTES_PER_LENGTH_OFFSET`.
-// allows overflow on 32-bit target
-#[allow(const_err)]
-pub const MAX_LENGTH_VALUE: usize = (1 << (BYTES_PER_LENGTH_OFFSET * 8)) - 1;
+#[cfg(target_pointer_width = "32")]
+pub const MAX_LENGTH_VALUE: usize = (std::u32::MAX >> 8 * (4 - BYTES_PER_LENGTH_OFFSET)) as usize;
+#[cfg(target_pointer_width = "64")]
+pub const MAX_LENGTH_VALUE: usize = (std::u64::MAX >> 8 * (8 - BYTES_PER_LENGTH_OFFSET)) as usize;
 
 /// Convenience function to SSZ encode an object supporting ssz::Encode.
 ///