Memory leak checking using Instruments on Mac

Question

I\'ve just been pulling my hair out trying to make Instruments cough up my deliberately constructed memory leaks. My test example looks like this:

class Lea         


        

Answer 1

Most unit testing code executes the desired code paths and exits. Although this is perfectly normal for unit testing, it creates a problem for the leaks tool, which needs time to analyze the process memory space. To fix this problem, you should make sure your unit-testing code does not exit immediately upon completing its tests. You can do this by putting the process to sleep indefinitely instead of exiting normally.

https://developer.apple.com/library/ios/documentation/Performance/Conceptual/ManagingMemory/Articles/FindingLeaks.html

Answer 2

Instruments, in Leaks mode can be really powerful for leak tracing, but I've found that it's more biased towards event-based GUI apps than command line programs (particularly those which exit after a short time). There used to be a CHUD API where you could programmatically control aspects of the instrumentation, but last time I tried it the frameworks were no longer provided as part of the SDK. Perhaps some of this is now replaced with Dtrace.

Also, ensure you're up to date with Xcode as there were some recent improvements in this area which might make it easier to do what you need. You could also keep the short delay before exit but make it conditional on the presence of an environment variable, and then set that environment variable in the Instruments launch properties for your app, so that running outside Instruments doesn't have the delay.

Answer 3

I've just decided to leave the 2 second delay during my debug+leaking build.