IOS: C ++ compiler warnings after upgrading to Xcode 8.3

I updated to Xcode 8.3 last week. I cannot get rid of this compiler warning:

ld: warning: direct access in function 'std::__1::basic_filebuf<char, std::__1::char_traits<char> >::open(char const*, unsigned int)' from file '/Path/To/Derived/Data/Xcode/DerivedData/myapp/Build/Intermediates/myapp.build/Debug-iphoneos/myapp.build/Objects-normal/arm64/myapp_lto.o' to global weak symbol 'std::__1::basic_filebuf<char, std::__1::char_traits<char> >::open(char const*, unsigned int)' from file '/Path/To/Derived/Data/Xcode/DerivedData/myapp/Build/Intermediates/myapp.build/Debug-iphoneos/myapp.build/Objects-normal/arm64/myapp_lto.o' means the weak symbol cannot be overridden at runtime. This was likely caused by different translation units being compiled with different visibility settings.

What I was trying to solve this warning:

• Change Symbols Hidden by Default
  
  to YES - for all purposes
• Change Symbols Hidden by Default
  
  to NO - for all purposes
• Essentially everything here (although not completely related)
• Clearing / deleting derived data / etc
• I added -fvisibility=hidden
  
  to my purpose, and also for all cocoapod purposes. ( here)

Any understanding is greatly appreciated. Thank you in advance.

UPDATE 2017-04-10:

This seems to be a problem caused by NewRelicAgent. Removing cocoapod from my project eliminates the warning. Studying this carefully.