set a breakpoint in malloc_error_break to debug

Question

For me here getting error :

[self.points addObject:@{@"latt": 
[NSNumber numberWithFloat:(latitudeString.floatValue)],@"long": [NSNumber numberWithFloat:(longitudeString.floatValue]}];

Like this: malloc: * error for object 0x7f8480743a00: pointer being freed was not allocated * set a breakpoint in malloc_error_break to debug

After adding malloc_error_break in Symbolic Breakpoint in Breakpoint Navigator getting same error

score 3 · Answer 1 · answered Apr 28 '17 at 18:27

For memory errors of this sort, ASAN (address sanitizer) can often be a helpful tool. It instruments your code so that it can catch incorrect uses of malloc & free where they happen, rather than later when they blow up. And it records the history of allocation & free events for a given address, so for instance if you had a double free, it would show you both free points.

You turn this on by editing the Run Scheme in Xcode, going to the Diagnostics tab, and turning on Address Sanitizer. This will require a rebuild, and the instrumented binaries will run a little slower, but generally not so much slower that you can't get your program to the point of failure.

score 0 · Answer 2 · edited May 23 '17 at 12:26

0

You can set a single "all exceptions breakpoint" like you can see here Exception Breakpoint in Xcode to find where the exception really comes from.

edited May 23 '17 at 12:26

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answered Apr 19 '17 at 07:57

Jérémy Voisin

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After using exception breakpoint again this error malloc: *** error for object 0x7ff02c3af000: double free *** set a breakpoint in malloc_error_break to debug (lldb) – Naresh Apr 19 '17 at 09:33
Are you using ARP ? – Jérémy Voisin Apr 19 '17 at 09:39
Not using ARP and i dont know what is ARP – Naresh Apr 19 '17 at 09:48
In your main.m, you should see @autoreleasepool. If so, you're using ARP (the auto reference counter) – Jérémy Voisin Apr 19 '17 at 09:50
I have this lines in main.m #import #import "AppDelegate.h" int main(int argc, char * argv[]) { @autoreleasepool { return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class])); } } – Naresh Apr 19 '17 at 09:52
Well, so you're using it :) Is your failing code inside any kind of loop ? – Jérémy Voisin Apr 19 '17 at 09:54
Failing inside the For Loop – Naresh Apr 19 '17 at 10:06
Is it a for...in loop? – Jérémy Voisin Apr 19 '17 at 10:07
Yes but a for(Classname* varname in collection) type of for? – Jérémy Voisin Apr 19 '17 at 10:11
If so, you should set a __strong before Varname or classname to avoid ARP freeing your variable – Jérémy Voisin Apr 19 '17 at 10:12
Here iam getting error . for (int i=0; i<[latitudeArray count]; i++) { NSNumber *latStr=[latitudeArray objectAtIndex:i]; NSNumber *longStr=[longitudeArray objectAtIndex:i]; [self.points addObject:@{@"latt": [NSNumber numberWithFloat:latStr.floatValue],@"long": [NSNumber numberWithFloat:longStr.floatValue]}]; – Naresh Apr 19 '17 at 10:13
Can you "__strongify" your in loop created NSNumber ? – Jérémy Voisin Apr 19 '17 at 10:17
I have changed longStr and latStr NSNumber to @property (strong, nonatomic) NSNumber *latStr,*longStr; again getting the same problem. – Naresh Apr 19 '17 at 10:22
Are your longitude and latitude array the same size ? Why don't you just set the i th NSNumber without any tranformation in your this.points? – Jérémy Voisin Apr 19 '17 at 10:30
latitude and longitude are same size .. How to set the i th NSNumber without any tranformation in this.points? – Naresh Apr 19 '17 at 10:34
In your code, what you do first is to get your i th element's float value then, you set, in your this.points, a NSNumber with float. Finally, it's just the same thing that set the i th element of your array in your associative array right ? – Jérémy Voisin Apr 19 '17 at 10:40

set a breakpoint in malloc_error_break to debug

2 Answers2