Instruments: Dispatch instrument can't be used (disables Record button)

Originator:Jens.Alfke
Number:rdar://20727517 Date Originated:28-Apr-2015 08:43 AM
Status:Open Resolved:
Product:Developer Tools Product Version:Xcode 6.3.1
Classification:Serious Bug Reproducible:Always
 
Summary:
It’s impossible to use the Dispatch instrument: adding it to the instrument list disables the Record button, so no data can be recorded. There is no UI feedback other than the disabled button so I have absolutely no idea what the underlying issue is.

Steps to Reproduce:
1. Open my iOS app project in Xcode and choose Product>Profile (Cmd-I)
2. In Instruments I select the Time Profiler template
3. I open the library and drag the Dispatch template into the instrument list
4. I press the Record button

Expected Results:
Instruments launches the app and starts recording data

Actual Results:
Nothing happens because the Record button is now disabled (after step 3)

Notes:
Removing the Dispatch instrument re-enables the Record button. It appears Instruments has decided I’ve created a state in which I can’t record, but there is absolutely no indication of why this happened or how to correct it.

Comments


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