win: fixes for Windows x64

minidump/minidump_thread_id_map.cc

 // Copyright 2014 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
 #include "minidump/minidump_thread_id_map.h"
 
 #include <limits>
 #include <set>
 #include <utility>
 
 #include "base/logging.h"
+#include "base/numerics/safe_conversions.h"
 #include "snapshot/thread_snapshot.h"
 
 namespace crashpad {
 
 void BuildMinidumpThreadIDMap(
     const std::vector<const ThreadSnapshot*>& thread_snapshots,
     MinidumpThreadIDMap* thread_id_map) {
   DCHECK(thread_id_map->empty());
 
   // First, try truncating each 64-bit thread ID to 32 bits. If that’s possible
@@ skipping 15 matching lines @@
   }
 
   if (collision) {
     // Since there was a collision, go back and assign each unique 64-bit thread
     // ID its own sequential 32-bit equivalent. The 32-bit thread IDs will not
     // bear any resemblance to the original 64-bit thread IDs.
     thread_id_map->clear();
     for (const ThreadSnapshot* thread_snapshot : thread_snapshots) {
       uint64_t thread_id_64 = thread_snapshot->ThreadID();
       if (thread_id_map->find(thread_id_64) == thread_id_map->end()) {
-        uint32_t thread_id_32 = thread_id_map->size();
+        uint32_t thread_id_32 =
+            base::checked_cast<uint32_t>(thread_id_map->size());
         thread_id_map->insert(std::make_pair(thread_id_64, thread_id_32));
       }
     }
 
     DCHECK_LE(thread_id_map->size(), std::numeric_limits<uint32_t>::max());
   }
 }
 
 }  // namespace crashpad