How to break on __NSAutoreleaseNoPool

I'm getting peppered with

*** __NSAutoreleaseNoPool(): Object 0x1961180 of class NSEvent autoreleased with no pool in place - just leaking

warnings during run-time and have no idea what the cause is. Cursory Googles indicate that this is a symbol I can break on with Xcode, but adding it as a symbolic breakpoint via Run>Manage Breakpoints>Add Symbolic Breakpoint, or simply via the breakpoints management window, results in a breakpoint with a - next to it instead of a check, which I take to mean it's a symbol that can't be found.

I've tried adding the symbol "__NSAutoreleaseNoPool" with two underscores, one underscore, and now I'm just feeling stupid. The errors continue to get logged and no开发者_StackOverflow breakpoints get hit. Any pointers for breaking on Obj-C symbols or debugging this would be appreciated.

[EDIT: after maybe 10 (10 more, so a couple dozen total, including at least two Xcode restarts) runs I got "Pending breakpoint 9 - "__NSAutoreleaseNoPool" resolved" printed to my console and the breakpoint started working. Is there any way to force a pending breakpoint to actually resolve?]

To actually answer your question, look in NSDebug.h. There you will find a comment of which this is part:

NAME OF ENV. VARIABLE                  DEFAULT  SET TO...
NSDebugEnabled                            NO    "YES"
NSZombieEnabled                           NO    "YES"
NSDeallocateZombies                       NO    "YES"
NSHangOnUncaughtException                 NO    "YES"

and farther down are these comments:

// Functions used as interesting breakpoints in a debugger
// void __NSAutoreleaseNoPool(void *object);
        // Called to log the "Object X of class Y autoreleased with no
        // pool in place - just leaking" message.  If an environment
        // variable named "NSAutoreleaseHaltOnNoPool" is set with string
        // value "YES", the function will automatically break in the
        // debugger (or terminate the process).

// void __NSAutoreleaseFreedObject(void *freedObject);
        // Called when a previously freed object would be released
        // by an autorelease pool.  If an environment variable named
        // "NSAutoreleaseHaltOnFreedObject" is set with string value
        // "YES", the function will automatically break in the debugger
        // (or terminate the process).

So you don't really need to set these breakpoints; just set the appropriate environment variables. You can do the latter either from your e.g. .bashrc or in Xcode 4 you can edit the "Run" section of your "scheme" and set them there -- that's what I do, and it works just fine.

I have the same issue on setting breakpoint on __NSAutoreleaseNoPool(). I finally successfully set the break point use gdb command. After debugger started, press ctrl+C in debugger console. Use "br __NSAutoreleaseNoPool" to set the break point and restart the debugger.

It sounds like you're using Cocoa in a thread somewhere and not wrapping the thread body with an autorelease pool. You probably don't need to use breakpoints to find this. Are you doing any detachNewThreadSelector?

The issue here is simple: You are releasing with no pool in place. This usually happens in command line tools written against Foundation. Simply add the following code to your main(): (Irrelevant parts omitted)

int main (…) {
  NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];

  /// Your code goes here.

  [pool drain]; // This one might not strictly speaking be neccessary.
  [pool release];

   return 0;
}

Edit: If you are not creating a command line tool, chances are you are doing something naughty; but nonetheless: If you have code you invoke before NSApplicationMain(), you need to wrap this in the same basic code, draining and releasing the pool before the invocation of NSApplicationMain.

I know this is an old thread. Just wanted to share some light on the right solution. The right way to have a breakpoint at _autoreleasenopool is using the breakpoint navigator in xcode.(use the key command+6). In the bottom left portion of the breakpoint navigator click '+' sign and add symbolic breaakpoint. Enter the symbol as objc_autoreleaseNoPool.