how to activate DEBUG_STACK_LEAK

I got this error:
TLS Allocator ALLOC_TEMP_THREAD, underlying allocator ALLOC_TEMP_THREAD has unfreed allocations, size 4080
and the console note said:
To Debug, enable the define: DEBUG_STACK_LEAK in StackAllocator.h. This will output the callstacks of the leaked allocations
I’d like to try that, but I can’t find “StackAllocator.h” in any of the project files.
The leak started when I added a scene to the project, and then requested “Generate lighting” in response to messages saying that this was necessary due to a lighting file incompatibility. But post hoc doesn’t imply propter hoc, as they say.

@j-millen After doing some research it’s a kind of memory leak error and there’s few ways to get over this

  1. Restart Unity , yup it helps sometimes if it is still there follow below
  2. If you are building the game for ios or android try removing the builds idk why but it fixes the error sometimes
  3. If the script causing the issue has Coroutines in it try commenting them out and see if that’s what sucking up so much memory
  4. If nothing works reimport all your assets.
    (Assets>Reimport All)
    Clean all the Console Warnings
    hit play