compiler warning for casting away const qualifier

[SjoerdMeijer]

Summary

This fix avoids compiler warnings about casting away const qualifiers.

[mehdi_amini]

Hey thanks for fixing behind me :)

LGTM.

lib/Bitcode/Writer/BitcodeWriter.cpp

void ModuleBitcodeWriter::writeIdentificationBlock() {
   Stream.EmitRecord(bitc::IDENTIFICATION_CODE_EPOCH, Vals, EpochAbbrev);
   Stream.ExitBlock();
 }
 
 void ModuleBitcodeWriter::writeModuleHash(size_t BlockStartPos) {
   // Emit the module's hash.
   // MODULE_CODE_HASH: [5*i32]
   SHA1 Hasher;
-  Hasher.update(ArrayRef<uint8_t>((uint8_t *)&(Buffer)[BlockStartPos],
+  Hasher.update(ArrayRef<uint8_t>((const uint8_t *)&(Buffer)[BlockStartPos],
                                   Buffer.size() - BlockStartPos));
   auto Hash = Hasher.result();
   SmallVector<uint64_t, 20> Vals;
   auto LShift = [&](unsigned char Val, unsigned Amount)
                     -> uint64_t { return ((uint64_t)Val) << Amount; };
   for (int Pos = 0; Pos < 20; Pos += 4) {
     uint32_t SubHash = LShift(Hash[Pos + 0], 24);
     SubHash |= LShift(Hash[Pos + 1], 16) | LShift(Hash[Pos + 2], 8) |

lib/LTO/ThinLTOCodeGenerator.cpp

#endif
     // Include the hash for every module we import functions from
     for (auto &Entry : ImportList) {
       auto ModHash = Index.getModuleHash(Entry.first());
       Hasher.update(ArrayRef<uint8_t>((uint8_t *)&ModHash[0], sizeof(ModHash)));
     }
 
     // Include the hash for the resolved ODR.
     for (auto &Entry : ResolvedODR) {
-      Hasher.update(ArrayRef<uint8_t>((uint8_t *)&Entry.first,
+      Hasher.update(ArrayRef<uint8_t>((const uint8_t *)&Entry.first,
                                       sizeof(GlobalValue::GUID)));
-      Hasher.update(ArrayRef<uint8_t>((uint8_t *)&Entry.second,
+      Hasher.update(ArrayRef<uint8_t>((const uint8_t *)&Entry.second,
                                       sizeof(GlobalValue::LinkageTypes)));
     }
 
     // Include the hash for the preserved symbols.
     for (auto &Entry : PreservedSymbols) {
       if (DefinedFunctions.count(Entry))
         Hasher.update(
-            ArrayRef<uint8_t>((uint8_t *)&Entry, sizeof(GlobalValue::GUID)));
+            ArrayRef<uint8_t>((const uint8_t *)&Entry, sizeof(GlobalValue::GUID)));
     }
 
     sys::path::append(EntryPath, CachePath, toHex(Hasher.result()));
   }
 
   // Access the path to this entry in the cache.
   StringRef getEntryPath() { return EntryPath; }