Environment: OS X macOS Sierra 10.12.2, Xcode 8.2.1, iPhone 7 running 10.2, app written in Swift.
I'm having a chronic problem where log messages from my app only show in the Xcode log window the first time I run the app after booting the phone.
If I rebuild and run the app again, the messages don't appear.
The issue persists whether I use NSLog or Swift's print statement to print the messages. If I use NSLog they show up in the Console app, and that's an OK workaround - except one of the third-party libraries I use apparently uses "print" or equivalent to write messages to stdout/stderr.
Has anyone else seen this issue? It's pretty chronic across my team here; I'm surprised I haven't seen other messages about it...
-David