brew: Error al establecer filetime 1503098583 en outfile: errno 1

Ahora veo a menudo un nuevo error al invocar brew. Funciona de todos modos, pero me pregunto cómo arreglar Failed to set filetime on outfile: errno 1

brew install redis                      
Failed to set filetime 1503098583 on outfile: errno 1          
Failed to set filetime 1500719840 on outfile: errno 1          
Failed to set filetime 1503105755 on outfile: errno 1          
Failed to set filetime 1503098357 on outfile: errno 1          
Failed to set filetime 1503115442 on outfile: errno 1          
Failed to set filetime 1499154411 on outfile: errno 1          
Updating Homebrew...           
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Updated 3 taps (caskroom/cask, cloudfoundry/tap, homebrew/core).                                                               
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