BoringSSL error:

if target.name == 'BoringSSL-GRPC'
      target.source_build_phase.files.each do |file|
        if file.settings && file.settings['COMPILER_FLAGS']
          flags = file.settings['COMPILER_FLAGS'].split
          flags.reject! { |flag| flag == '-GCC_WARN_INHIBIT_ALL_WARNINGS' }
          file.settings['COMPILER_FLAGS'] = flags.join(' ')
        end
      end
    end

Comments