There are a couple questions with the same keywords as the title, however they focus on the iOS side of Objective-C. My problem is with a MacOS command line tool.
Basically what's happening is that the Foundation (Cocoa) tool is calling a C function which ends up calling another Foundation method. And as the Foundation method is being called from the C function, that's where the "Symbol not found: _objc_retainAutoreleasedReturnValue" error is being thrown at run time.
The code looks like this:
log.h
@interface Log : NSObject {
}
@end
void RemoveLogFile(NSString * theLogFile);
log.m
#import "Log.h"
@implementation Log
@end
// this is a C-style function
void RemoveLogFile(NSString * theLogFile)
{
NSString * logFileName;
NSLog( @"about to allocate a filename" );
// crash can happen in either case below
#if 1
logFileName = [NSString stringWithFormat: @"%@.log", theLogFile];
#else
logFileName = [[NSString alloc] initWithFormat: @"%@.log", theLogFile];
#endif
NSLog( @"done allocating");
}
main.m
#import <Foundation/Foundation.h>
#import "Log.h"
int main(int argc, const char * argv[])
{
@autoreleasepool {
NSString* outPath = [[NSString alloc] initWithFormat: @"%@/MyLogFile", @"/tmp/"];
NSLog( @"past out path alloc");
RemoveLogFile(outPath);
NSLog( @"done with the test");
}
return 0;
}
ARC is turned on for the 64-bit compiled tool (it can't be turned on for the 32-bit version) and the minimum supported MacOS version is 10.6.
When the tool is called in MacOS 10.7, it promptly crashes out with a log like this:
Process: com.dautermann.Doughnuts [540]
Path: /Library/PrivilegedHelperTools/com.dautermann.Doughnuts
Identifier: com.dautermann.Doughnuts
Version: ??? (1.0)
Code Type: X86-64 (Native)
Parent Process: launchd [1]
Date/Time: 2013-02-19 05:02:48.337 -0800
OS Version: Mac OS X 10.7 (11A390)
Report Version: 8
Crashed Thread: 0 Dispatch queue: com.apple.main-thread
Exception Type: EXC_BREAKPOINT (SIGTRAP)
Exception Codes: 0x0000000000000002, 0x0000000000000000
Application Specific Information:
objc[540]: garbage collection is OFF
Dyld Error Message:
Symbol not found: _objc_retainAutoreleasedReturnValue
Referenced from: /Library/PrivilegedHelperTools/com.dautermann.Doughnuts
Expected in: /usr/lib/libobjc.A.dylib
Thread 0 name: Dispatch queue: com.apple.main-thread
Thread 0 Crashed:
0 dyld 0x00007fff5fc0106d dyld_fatal_error + 1
1 dyld 0x00007fff5fc04918 dyld::fastBindLazySymbol(ImageLoader**, unsigned long) + 128
2 libdyld.dylib 0x00007fff925f0716 dyld_stub_binder_ + 13
3 ??? 0x0000000100004030 0 + 4294983728
4 com.dautermann.Doughnuts 0x0000000100001523 0x100000000 + 5411
5 com.dautermann.Doughnuts 0x0000000100001470 0x100000000 + 5232
My educated guess (with help from other folks) is that I may need to either pass in a "char *", or I have to declare something somewhere as "_unsafe_unretained". It sure seems like something that the modern Xcode 4.6 compiler should be handling for me.
Anyone have any guesses as to what I might be doing wrong?
