Merge pull request #5490

6bd0dc2 arith_uint256: remove initialization from byte vector (Wladimir J. van der Laan)
30007fd Remove now-unused methods from arith_uint256 and base_uint (Wladimir J. van der Laan)
edc7204 Remove arith_uint160 (Wladimir J. van der Laan)
dba2e91 Add tests for new uint256 (Wladimir J. van der Laan)
92cdb1a Add conversion functions arith_uint256<->uint_256 (Wladimir J. van der Laan)
bfc6070 uint256->arith_uint256 blob256->uint256 (Wladimir J. van der Laan)
734f85c Use arith_uint256 where necessary (Wladimir J. van der Laan)
34cdc41 String conversions uint256 -> uint256S (Wladimir J. van der Laan)
2eae315 Replace uint256(1) with static constant (Wladimir J. van der Laan)
8076585 Replace GetLow64 with GetCheapHash (Wladimir J. van der Laan)
4f15249 Replace direct use of 0 with SetNull and IsNull (Wladimir J. van der Laan)
5d3064b Temporarily add SetNull/IsNull/GetCheapHash to base_uint (Wladimir J. van der Laan)

1 files changed, 8 insertions, 7 deletions

diff --git a/src/pow.cpp b/src/pow.cpp
index e91e3d893..90bbff0a3 100644
--- a/src/pow.cpp
+++ b/src/pow.cpp
@@ -5,6 +5,7 @@
 
 #include "pow.h"
 
+#include "arith_uint256.h"
 #include "chain.h"
 #include "chainparams.h"
 #include "primitives/block.h"
@@ -56,8 +57,8 @@ unsigned int GetNextWorkRequired(const CBlockIndex* pindexLast, const CBlockHead
         nActualTimespan = Params().TargetTimespan()*4;
 
     // Retarget
-    uint256 bnNew;
-    uint256 bnOld;
+    arith_uint256 bnNew;
+    arith_uint256 bnOld;
     bnNew.SetCompact(pindexLast->nBits);
     bnOld = bnNew;
     bnNew *= nActualTimespan;
@@ -79,7 +80,7 @@ bool CheckProofOfWork(uint256 hash, unsigned int nBits)
 {
     bool fNegative;
     bool fOverflow;
-    uint256 bnTarget;
+    arith_uint256 bnTarget;
 
     if (Params().SkipProofOfWorkCheck())
        return true;
@@ -91,22 +92,22 @@ bool CheckProofOfWork(uint256 hash, unsigned int nBits)
         return error("CheckProofOfWork() : nBits below minimum work");
 
     // Check proof of work matches claimed amount
-    if (hash > bnTarget)
+    if (UintToArith256(hash) > bnTarget)
         return error("CheckProofOfWork() : hash doesn't match nBits");
 
     return true;
 }
 
-uint256 GetBlockProof(const CBlockIndex& block)
+arith_uint256 GetBlockProof(const CBlockIndex& block)
 {
-    uint256 bnTarget;
+    arith_uint256 bnTarget;
     bool fNegative;
     bool fOverflow;
     bnTarget.SetCompact(block.nBits, &fNegative, &fOverflow);
     if (fNegative || fOverflow || bnTarget == 0)
         return 0;
     // We need to compute 2**256 / (bnTarget+1), but we can't represent 2**256
-    // as it's too large for a uint256. However, as 2**256 is at least as large
+    // as it's too large for a arith_uint256. However, as 2**256 is at least as large
     // as bnTarget+1, it is equal to ((2**256 - bnTarget - 1) / (bnTarget+1)) + 1,
     // or ~bnTarget / (nTarget+1) + 1.
     return (~bnTarget / (bnTarget + 1)) + 1;