Merge #13258: uint256: Remove unnecessary crypto/common.h dependency

bf2e01097 uint256: Remove unnecessary crypto/common.h use (Karl-Johan Alm)

Pull request description:

  This is an alternative to #13242 which keeps the `ReadLE64` part, but moves the `crypto/common.h` dependency into `crypto/common.h` as a function outside of `uint256`.

  **Reason:** this change will remove dependencies for `uint256` to `crypto/common.h`, `compat/endian.h`, and `compat/byteswap.h`.

  This PR removes the need to update tests to be endian-aware/-independent, but keeps the (arguably dubious) `ReadLE64` part (which was only introduced to fix the tests, not for any functionality).

Tree-SHA512: 78b35123cdb185b3b3ec59aba5ca8a5db72624d147f2d6a5484ffa5ce626a72f782a01dc6893fc8f5619b03e2eae7b5a03b0df5d43460f3bda428e719e188aec

1 files changed, 5 insertions, 1 deletions

diff --git a/src/validation.h b/src/validation.h
index 3e98ebc866..b5548a9293 100644
--- a/src/validation.h
+++ b/src/validation.h
@@ -12,6 +12,7 @@
 
 #include <amount.h>
 #include <coins.h>
+#include <crypto/common.h> // for ReadLE64
 #include <fs.h>
 #include <protocol.h> // For CMessageHeader::MessageStartChars
 #include <policy/feerate.h>
@@ -138,7 +139,10 @@ static const int DEFAULT_STOPATHEIGHT = 0;
 
 struct BlockHasher
 {
-    size_t operator()(const uint256& hash) const { return hash.GetCheapHash(); }
+    // this used to call `GetCheapHash()` in uint256, which was later moved; the
+    // cheap hash function simply calls ReadLE64() however, so the end result is
+    // identical
+    size_t operator()(const uint256& hash) const { return ReadLE64(hash.begin()); }
 };
 
 extern CScript COINBASE_FLAGS;