Xcode Instruments is stripping symbols despite all build settings to the contrary

问题

Problem

Instruments' Time Profiler is stripping all symbols except system libraries from my app, despite the fact that I have disabled this behavior in all relevant build settings in Xcode — but only on one development machine. The other dev machine behaves normally.

Description

Instruments' Time Profiler is stripping all symbols except system libraries, despite the fact that I have disabled this behavior in all relevant build settings in Xcode — but this is only happening on one of my development machines. I have two development machines running the same version of OS X, Xcode, and Instruments, and each machine is using an identical copy of the same Xcode project with identical build settings, schemes, and other configurations, and the app is profiled using the same test device (iPhone 4S with the latest public version of iOS 5).

Machine 1
- Mac OS X 10.7.4
- Xcode 4.3.2 (4E2002)
- Instruments 4.3 (4321)

Machine 2
- Mac OS X 10.7.4
- Xcode 4.3.2 (4E2002)
- Instruments 4.3 (4321)

Steps To Reproduce

Open included sample project on each machine.
Make sure the iPhone 4S is selected as the test device.
Select Product > Profile
When Instruments launches, select Time Profiler and continue.
Run the app.
Notice how the symbols are stripped when running on the iMac (Machine 1) but not on the MacBook Air (Machine 2).

Expected Behavior

Symbols from my own code should appear in the Time Profiler on both machines.

Regression

I have tried all of the following, with no change in the actual results:

Rebooting the machine.
Trying other Xcode projects
Deleting the "Derived Data" for all projects in the Xcode Organizer.
Re-symbolicating the document in Instruments (carefully selecting the correct DSYM file in ~/Library/blahBlahBlah…)

Final Notes

Here is a link to a .zip file of a sample project: Sample Project .zip

回答1:

I was finally able to get it to work by a method that's just shy of a nuke-and-pave scenario:

Make absolutely sure all symbol stripping is disabled for your current build configuration. Make sure you've done this for your Release config if that's what's being profiled for Instruments.
Delete the app from the iOS device.
Restart the iOS device.
Restart the Mac (I don't trust Xcode or Lion at all to quit all relevant processes otherwise).
Launch Xcode, go to Organizer > Projects and delete Derived Data for the affected project.
Clean your project. Hell, why not?
Build and profile for Instruments.
Choose the Time Profiler in Instruments for clarity.
The first run will not show the symbols, but don't quit. Leave Instruments running!
Re-symbolicate the document in Instruments, navigating carefully to the correct dSYM file for the current build. This should be easier since you've deleted the derived data in step 5.
Now you should be able to see your symbols. It helps if you hide non-objective-C symbols.

Why do I suggest that you delete the app and restart the iOS device in Steps 2 and 3? I have a suspicion that Xcode doesn't perform a clean installation of each build, but may install deltas, such that the symbol addresses present in Instruments are a mixture of the current build plus previous builds. If so, then this issue is even more common for someone like me, who shares a single test device between more than one Mac. This assumption could be wildly incorrect.

If the above steps don't work for you, please let me know in the comments. I'd like to create a detailed radar report at some point in the future.

回答2:

I'm not sure that it has been fixed in the 4.3 but this is a known problem in 4.2 seen here

Instruments There is a known issue with the Profile action from Xcode 4.2. After a build in which no source files have changed, Instruments will be unable to gather symbols for the target application.

This affects projects where both:

The Release configuration is selected for the Profile action. (default)
The Strip Linked Product build setting is set to "Yes”, or a custom Run Script build phase strips the product. (non-default)

The workaround is to do any one of the following:

Perform a "Clean" on the product before initiating the Profile action.
Do a Clean of the product and temporarily set the Strip Linked Product build setting to "No" while Profiling.
Set the configuration of the Profile action to Debug.
Run successive profiles directly from within Instruments when you do not need to rebuild. When developing Mac apps, using the GC Monitor template in Instruments may cause Instruments to crash. To workaround the problem please consider migrating your application to ARC.

回答3:

I've had a similar problem for days. I was able to profile the Debug configuration, but not Release. First I tried to make a copy of the release configuration (as suggested somewhere on the web), but that copy did not work either.

Then I made a copy of Debug, called it Profile, tried it and the symbols of Profile were shown in the profiler. Great! I then changed the optimization levels etc. to the same as Release, and now it works! Just wanted to share this, as this comment would have spared me hours...

回答4:

Have been facing the same and stumbled upon this thread.

I realized that I first profiled the app with release build and after changing the scheme in Xcode for the same app, the profiler was still unable to symbolize. I have tried all obvious solutions you mentioned above but in vain.

The profiler somehow is still referring to the first build (release build)'s settings and hence it is not able to symbolize. So, I just changed the app's bundle identifier for testing purpose so that a new app is created altogether for profiling purpose. I could check the code where leaks exist now.

Try it out and let me know if this works for you too. Still pondering over why Instruments is failing to symbolize though.

回答5:

I had a similar issue where I had no symbols in my os x application that I built from the command line (so in this case it is not an iphone or xcode issue). It turned out the problem was due to a bad DYLD_LIBRARY_PATH that contained my PATH. When I got rid of all those non-library paths, such as /usr/bin/, it worked.

回答6:

I have a lot of third party frameworks whose symbols and binaries are unfortunately getting lost.

Additionally, my app's binary was getting lost.

I.e. if I selected File > Symbols, clicked my target, and found the similarly named item, the Binary Path was showing up red.

The solution was to go to Instruments > Preferences > Symbols, and add /Users/<MY_USER>/Library/Developer/Xcode/DerviedData to the search paths. Library is not indexed by Spotlight. After doing this, I have at least had the symbols for my app. The little circle next to my app's name goes from Yellow to Green when I do this, and persists between restarting Instruments, unlike other solutions to manually set the binary.

Let me know if you can tell me how to get all the ones for my third party frameworks. I use Carthage for some, others installed manually. Have had no luck with these yet.