How to find the cause of a malloc “double free” error?

Question

I\'m programming an application in Objective-C and I\'m getting this error:

MyApp(2121,0xb0185000) malloc: *** error for object 0x1068310: double

Answer 1

You'll find out what the object is when you break in the debugger. Just look up the call stack and you will find where you free it. That will tell you which object it is.

The easiest way to set the breakpoint is to:

1. Go to Run -> Show -> Breakpoints (ALT-Command-B)
2. Scroll to the bottom of the list and add the symbol malloc_error_break