merkle-tree: fix build when targeting bpf (bp #16335)

merkle-tree/Cargo.toml

@@ -10,9 +10,13 @@ documentation = "https://docs.rs/solana-merkle-tree"
 edition = "2018"
 
 [dependencies]
-solana-sdk = { path = "../sdk", version = "=1.6.5" }
+solana-program = { path = "../sdk/program", version = "=1.6.5" }
 fast-math = "0.1"
 
+# This can go once the BPF toolchain target Rust 1.42.0+
+[target.bpfel-unknown-unknown.dependencies]
+matches = "0.1.8"
+
 [dev-dependencies]
 hex = "0.4.2"
 

merkle-tree/Xargo.toml

@@ -0,0 +1,2 @@
+[target.bpfel-unknown-unknown.dependencies.std]
+features = []

merkle-tree/src/lib.rs

@@ -1,3 +1,8 @@
 #![allow(clippy::integer_arithmetic)]
+
+#[cfg(target_arch = "bpf")]
+#[macro_use]
+extern crate matches;
+
 pub mod merkle_tree;
 pub use merkle_tree::MerkleTree;

merkle-tree/src/merkle_tree.rs

@@ -1,4 +1,4 @@
-use solana_sdk::hash::{hashv, Hash};
+use solana_program::hash::{hashv, Hash};
 
 // We need to discern between leaf and intermediate nodes to prevent trivial second
 // pre-image attacks.