Merge bitcoin#24146: Avoid integer sanitizer warnings in chain.o

fa83210 Avoid integer sanitizer warnings in chain.o (MarcoFalke)

Pull request description:

  The two changes make the code more self-documenting and also allow to remove 5 file-wide suppressions for the module

ACKs for top commit:
  PastaPastaPasta:
    utACK fa83210
  jonatack:
    ACK fa83210

Tree-SHA512: d32a06099c56eed9f69130a3209f989872acc593f849528acd7746ee6caa96688cc32de37e8e59ad5d25dcb8912e341f1a43e50642dadeff6ca7624d0873ad10

Author: MarcoFalke

src/chain.cpp

@@ -151,7 +151,7 @@ int64_t GetBlockProofEquivalentTime(const CBlockIndex& to, const CBlockIndex& fr
     if (r.bits() > 63) {
         return sign * std::numeric_limits<int64_t>::max();
     }
-    return sign * r.GetLow64();
+    return sign * int64_t(r.GetLow64());
 }
 
 /** Find the last common ancestor two blocks have.

src/chain.h

@@ -475,7 +475,7 @@ class CChain
     /** Return the maximal height in the chain. Is equal to chain.Tip() ? chain.Tip()->nHeight : -1. */
     int Height() const
     {
-        return vChain.size() - 1;
+        return int(vChain.size()) - 1;
     }
 
     /** Set/initialize a chain with a given tip. */

test/sanitizer_suppressions/ubsan

@@ -46,8 +46,6 @@ shift-base:test/fuzz/crypto_diff_fuzz_chacha20.cpp
 unsigned-integer-overflow:addrman.cpp
 unsigned-integer-overflow:arith_uint256.h
 unsigned-integer-overflow:common/bloom.cpp
-unsigned-integer-overflow:chain.cpp
-unsigned-integer-overflow:chain.h
 unsigned-integer-overflow:coins.cpp
 unsigned-integer-overflow:compressor.cpp
 unsigned-integer-overflow:core_write.cpp
@@ -63,8 +61,6 @@ unsigned-integer-overflow:validation.cpp
 implicit-integer-sign-change:addrman.h
 implicit-integer-sign-change:bech32.cpp
 implicit-integer-sign-change:common/bloom.cpp
-implicit-integer-sign-change:chain.cpp
-implicit-integer-sign-change:chain.h
 implicit-integer-sign-change:coins.h
 implicit-integer-sign-change:compat/stdin.cpp
 implicit-integer-sign-change:compressor.h
@@ -79,10 +75,8 @@ implicit-integer-sign-change:serialize.h
 implicit-integer-sign-change:test/streams_tests.cpp
 implicit-integer-sign-change:txmempool.cpp
 implicit-integer-sign-change:zmq/zmqpublishnotifier.cpp
-implicit-signed-integer-truncation,implicit-integer-sign-change:chain.h
 implicit-signed-integer-truncation:addrman.cpp
 implicit-signed-integer-truncation:addrman.h
-implicit-signed-integer-truncation:chain.h
 implicit-signed-integer-truncation:crypto/
 implicit-unsigned-integer-truncation:crypto/
 shift-base:arith_uint256.cpp