CaloCondBlobObjs: Fix unaligned writes.

CaloCondBlobObjs: Fix unaligned writes.

Fix potential unaligned writes of 64-bit quantities, using 
CxxUtils::set_unaligned.
Fixes UB sanitizer warnings seen in the dbg build.

Calorimeter/CaloCondBlobObjs/CMakeLists.txt

@@ -12,7 +12,7 @@ atlas_add_library( CaloCondBlobObjs
                    src/*.cxx
                    PUBLIC_HEADERS CaloCondBlobObjs
                    INCLUDE_DIRS ${CORAL_INCLUDE_DIRS}
-                   LINK_LIBRARIES ${CORAL_LIBRARIES} GaudiKernel
+                   LINK_LIBRARIES ${CORAL_LIBRARIES} GaudiKernel CxxUtils
                    PRIVATE_LINK_LIBRARIES AthenaKernel )
 
 atlas_add_dictionary( CaloCondBlobObjsDict

Calorimeter/CaloCondBlobObjs/CaloCondBlobObjs/CaloCondBlobBase.h

 /*
-  Copyright (C) 2002-2023 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2025 CERN for the benefit of the ATLAS collaboration
 */
 
 #ifndef CALOCONDBLOBOBJS_CALOCONDBLOBBASE_H
@@ -38,6 +38,7 @@
 #include "CoralBase/Blob.h"
 #include "CaloCondBlobObjs/Exception.h"
 #include "CaloCondBlobObjs/CaloCondType.h"
+#include "CxxUtils/get_unaligned.h"
 
 class CaloCondBlobBase{
  public:
@@ -283,8 +284,9 @@ inline uint64_t
 CaloCondBlobBase::getTimeStamp() const 
 {
   if(!getCommentSizeUint32()) return 0;
-  return *(reinterpret_cast<const uint64_t*>(getBlobStart()+getHdrSize() +
-                                             getNObjs()*getObjSizeUint32()));
+  auto p = reinterpret_cast<const uint8_t*>(getBlobStart()+getHdrSize() +
+                                            getNObjs()*getObjSizeUint32());
+  return CxxUtils::get_unaligned64 (p);
 }
 
 #endif

Calorimeter/CaloCondBlobObjs/src/CaloCondBlobBase.cxx

 /*
-  Copyright (C) 2002-2023 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2025 CERN for the benefit of the ATLAS collaboration
 */
 
 #include "CaloCondBlobObjs/CaloCondBlobBase.h"
 #include "CaloCondBlobObjs/CaloCondType.h"
+#include "CxxUtils/set_unaligned.h"
 #include <algorithm>
 #include <ctime>
 
@@ -121,9 +122,8 @@ CaloCondBlobBase::createBlob(uint16_t objType,
   //==== fill comment fields
   if(commentSizeChar){
     if(!timeStamp) timeStamp = ::time(nullptr);
-    uint64_t* pTimeStamp = reinterpret_cast<uint64_t*>(getBlobStart()+dataSizeByte/sizeof(uint32_t));
-    pTimeStamp[0] = timeStamp;
-    char* pChar = reinterpret_cast<char*>(++pTimeStamp); 
+    uint8_t* pChar = reinterpret_cast<uint8_t*> (getBlobStart()+dataSizeByte/sizeof(uint32_t));
+    CxxUtils::set_unaligned<uint64_t> (pChar, timeStamp);
     std::string::const_iterator iStr = author.begin();
     for(; iStr!=author.end(); ++iStr){ *pChar = *iStr; ++pChar; }
     *pChar = 0; 

Calorimeter/CaloCondBlobObjs/test/CaloCondBlobBase_test.cxx

 /*
-  Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2025 CERN for the benefit of the ATLAS collaboration
 */
 
 #define BOOST_TEST_DYN_LINK
@@ -11,6 +11,7 @@ namespace utf = boost::unit_test;
 
 #include "CaloCondBlobObjs/CaloCondBlobBase.h"
 #include "CoralBase/Blob.h"
+#include "CxxUtils/set_unaligned.h"
 #include <cstdint>
 #include <sstream> 
 #include <iostream>
@@ -117,13 +118,12 @@ BOOST_AUTO_TEST_CASE(PublicMethods, * utf::expected_failures(1)){
   pDestination[2] = num;
   pDestination[3] = 0x80000000 | (gain << 24) | nChans;
   pDestination[4] = comment.size() / wordSize;
-  uint64_t* pTimeStamp = reinterpret_cast<uint64_t*>(pDestination+dataSizeWord);
+  uint8_t* pChar = reinterpret_cast<uint8_t*>(pDestination+dataSizeWord);
   uint64_t timeStamp{0};
-  pTimeStamp[0] = timeStamp;
-  char* pChar = reinterpret_cast<char*>(++pTimeStamp); 
-  strcpy(pChar, author.c_str());
+  CxxUtils::set_unaligned<uint64_t> (pChar, timeStamp);
+  strcpy(reinterpret_cast<char*>(pChar), author.c_str());
   pChar+=(1+author.size());
-  strcpy(pChar, comment.c_str());
+  strcpy(reinterpret_cast<char*>(pChar), comment.c_str());
   //instantiate the class using this blob
   CaloCondBlobStub blobStub(b);
   //checking...