Floating-point values logged via os_log from Swift are wrong when viewed in Console app
| Originator: | jjc1138 | ||
| Number: | rdar://28763393 | Date Originated: | 2016-10-13 |
| Status: | Open | Resolved: | |
| Product: | macOS SDK | Product Version: | 10.12 (16A323) |
| Classification: | Other Bug | Reproducible: | Always |
Summary:
When a floating-point value is logged via os_log from Swift code the value appears wrong when viewing the log in the Console app. Interestingly it appears correct in the Xcode console.
Steps to Reproduce:
1. Build and run the attached trivial repro project, which just runs the following on launch:
os_log("%g", 0.1 as Double)
2. Open the Console app and filter for 'process:Swift Logging Test macOS' to find the log message.
3. Observe that the value in the logged message is wrong, and observe that the value in the Xcode console is correct
Expected Results:
0.1
Actual Results:
8.344027e-310
Version:
Xcode 8.0 (8A218a), macOS 10.12 (16A323)
Notes:
Configuration:
The same thing happens when running the app on the Mac itself, or when running an app on an attached iOS device. It doesn't happen when running an equivalent Objective-C test project.
Attachments:
'Swift Logging Test macOS.zip' was successfully uploaded.
Comments
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