[llvm] [BOLT] Fix counts aggregation in merge-fdata (PR #119652)

[Alexander Yermolovich via llvm-commits]

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@@ -330,14 +347,14 @@ void mergeLegacyProfiles(const SmallVectorImpl<std::string> &Filenames) {
   ProfileTy MergedProfile;
   for (const auto &[Thread, Profile] : ParsedProfiles)
     for (const auto &[Key, Value] : Profile) {
-      uint64_t Count = MergedProfile.lookup(Key) + Value;
+      auto Count = MergedProfile.lookup(Key) + Value;
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ayermolo wrote:

Why change to auto?

https://github.com/llvm/llvm-project/pull/119652