ios - malloc: *** error: incorrect checksum for freed object - object was probably modified after being freed

Question

I have a big problem with my iOS App: it crashes sometimes without detailed debug error. The stack trace is empty. These are the only two lines in the stack trace:

1. crash start in UIApplicationMain at "symbol stub for: -[_UIHostedTextServiceSession dismissTextServiceAnimated:]".
2. and report "libsystem_c.dylib`malloc_error_break".

in com.apple.main-thread.

The error on Xcode debugger (with connected device):

malloc: *** error for object 0x208a7614: incorrect checksum for freed object - object was probably modified after being freed.
*** set a breakpoint in malloc_error_break to debug

I have set a breakpoint in malloc_error_break with libsystem_c.dylib without any feedback from debugger. I have no idea to solve this issue.

Answer 1

To find the source of the problem, in Xcode go to Product > Scheme > Edit Scheme, and under Diagnostics tab enable all the Malloc settings and Guard Malloc.

With that, run your application again, and Xcode will stop at the line causing the problem.