SDK 3.7.5 Again AUv2 Crash on close

Developer VST 3 SDK
1

After 2 days of trying to get a working AUv3 version of the AGain project, I decided it would be prudent to try my luck with AUv2 instead.

Unfortunately even the AUv2 version is crashing on plugin removal. Any ideas?

Process:               Logic Pro X [2240]
Path:                  /Applications/Logic Pro X.app/Contents/MacOS/Logic Pro X
Identifier:            com.apple.logic10
Version:               10.6.3 (5458)
Build Info:            MALogic-5458000000000000~3 (10U159)
App Item ID:           634148309
App External ID:       841990097
Code Type:             X86-64 (Native)
Parent Process:        ??? [1]
Responsible:           Logic Pro X [2240]
User ID:               501

Date/Time:             2022-06-15 11:40:35.712 +0800
OS Version:            Mac OS X 10.15.7 (19H1519)
Report Version:        12
Bridge OS Version:     6.4 (19P4243)
Anonymous UUID:        B8DA52AB-9339-56BF-560C-8A553D8C34B7


Time Awake Since Boot: 910 seconds

System Integrity Protection: enabled

Crashed Thread:        0  Dispatch queue: com.apple.main-thread

Exception Type:        EXC_CRASH (SIGABRT)
Exception Codes:       0x0000000000000000, 0x0000000000000000
Exception Note:        EXC_CORPSE_NOTIFY

Termination Reason:    Namespace OBJC, Code 0x1

Application Specific Information:
Dublin | 6b34edbe1e2428234532a9a90f0dda622834cd344de3e01f645f6cf5be04bce1 | c226c3f729b55e358699a7f7b18f27a9803c1159 | 2021-07-07_15:09:24
 
Attempt to use unknown class 0x600000475290.

Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0   libsystem_kernel.dylib        	0x00007fff705e4ad6 __abort_with_payload + 10
1   libsystem_kernel.dylib        	0x00007fff705e63df abort_with_payload_wrapper_internal + 80
2   libsystem_kernel.dylib        	0x00007fff705e638f abort_with_reason + 19
3   libobjc.A.dylib               	0x00007fff6f2ec820 _objc_fatalv(unsigned long long, unsigned long long, char const*, __va_list_tag*) + 114
4   libobjc.A.dylib               	0x00007fff6f2ec7ae _objc_fatal(char const*, ...) + 135
5   libobjc.A.dylib               	0x00007fff6f2cfc37 lookUpImpOrForward + 802
6   libobjc.A.dylib               	0x00007fff6f2cf399 _objc_msgSend_uncached + 73
7   com.apple.AppKit              	0x00007fff3363dc47 _detach2 + 34
8   libobjc.A.dylib               	0x00007fff6f2ec054 AutoreleasePoolPage::releaseUntil(objc_object**) + 134
9   libobjc.A.dylib               	0x00007fff6f2d0dba objc_autoreleasePoolPop + 175
10  com.apple.CoreFoundation      	0x00007fff36333315 _CFAutoreleasePoolPop + 22
11  com.apple.Foundation          	0x00007fff389e503e -[NSAutoreleasePool drain] + 126
12  com.apple.AppKit              	0x00007fff335d8c12 -[NSApplication run] + 758
13  com.apple.AppKit              	0x00007fff335aa996 NSApplicationMain + 777
14  com.apple.logic10             	0x000000010663786d 0x105a88000 + 12253293
15  libdyld.dylib                 	0x00007fff70483cc9 start + 1
2

Some more details on this.

  • If the plugin is off or the the UI is closed, then there is no crash on plugin removal.
  • If more than one instance of the plugin is loaded, and they are removed such that the first instance is removed last, there is no crash.
3

I’m working macOS 10.15.7 and Xcode 12.4. Looking through the wrapper code, it looks like the code below is the culprit. MAC_OS_X_VERSION_10_11 is defined on my system. If I remove the workaround everything is fine.

            #if defined(MAC_OS_X_VERSION_10_11)
			// workaround, because CFBundleCreate returns refcount == 2.
			if (CFBundleIsExecutableLoaded ((CFBundleRef)instance))
			{
				CFBundleUnloadExecutable ((CFBundleRef)instance);
				CFRelease ((CFBundleRef)instance);
			}
            #else
			CFRelease ((CFBundleRef)instance);
            #endif