Xcode 12b2 crashes at launch with ASSERTION FAILURE in /Library/Caches/com.apple.xbs/Sources/DVTFrameworks/DVTFrameworks-17160.5/DVTFoundation/DeveloperStructure/DVTExtendedPlatformInfo.m:110

Xcode 12b2 crashes at launch on my machine. Xcode 12b1 works fine. Any idea ?

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

Exception Type: EXCCRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Exception Note: EXC
CORPSENOTIFY

Application Specific Information:
ProductBuildVersion: 12A6163b
ASSERTION FAILURE in /Library/Caches/com.apple.xbs/Sources/DVTFrameworks/DVTFrameworks-17160.5/DVTFoundation/DeveloperStructure/DVTExtendedPlatformInfo.m:110
Details: (extensionPoint) should not be nil.
Object: <DVTExtendedPlatformInfo>
Method: +extendedPlatformInfoForPlatformIdentifier:error:
Thread: <NSThread: 0x7fc86a51a8e0>{number = 1, name = main}
Open FDs: 6/256
Hints:

Backtrace:
0 -[IDEAssertionHandler handleFailureInMethod:object:fileName:lineNumber:assertionSignature:messageFormat:arguments:] (in IDEKit)
1
DVTAssertionHandler (in DVTFoundation)
2 DVTAssertionFailureHandler (in DVTFoundation)
3
75+[DVTExtendedPlatformInfo extendedPlatformInfoForPlatformIdentifier:error:]blockinvoke (in DVTFoundation)
4
dispatchclientcallout (in libdispatch.dylib)
5 dispatchoncecallout (in libdispatch.dylib)
6 +[DVTExtendedPlatformInfo extendedPlatformInfoForPlatformIdentifier:error:] (in DVTFoundation)
7 -[DVTPlatform(DVTExtendedPlatformInfo) dvt
extendedInfoOrError:] (in DVTFoundation)
8 +[DVTPlatform validatePlatformDataReturningError:] (in DVTFoundation)
9 IDEInitialize (in IDEFoundation)
10 -[IDEApplicationController applicationWillFinishLaunching:] (in IDEKit)
11 CFNOTIFICATIONCENTERISCALLINGOUTTOANOBSERVER (in CoreFoundation)
12 __CFXRegistrationPost1blockinvoke (in CoreFoundation)
13
CFXRegistrationPost1 (in CoreFoundation)
14 __CFXNotificationPostblockinvoke (in CoreFoundation)
15 -[
CFXNotificationRegistrar find:object:observer:enumerator:] (in CoreFoundation)
16 CFXNotificationPost (in CoreFoundation)
17 -[NSNotificationCenter postNotificationName:object:userInfo:] (in Foundation)
18 -[NSNotificationCenter(DVTNSNotificationCenterAdditions
MRR) dvtpostNotificationName:object:userInfo:] (in DVTFoundation)
19 -[NSApplication finishLaunching] (in AppKit)
20 -[DVTApplication finishLaunching] (in DVTKit)
21 -[NSApplication run] (in AppKit)
22 NSApplicationMain (in AppKit)
23 start (in libdyld.dylib)

abort() called

Application Specific Signatures:
((extensionPoint)) != nil

Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0 libsystemkernel.dylib 0x00007fff6e60533a pthreadkill + 10
1 libsystempthread.dylib 0x00007fff6e6c5e60 pthreadkill + 430
2 libsystemc.dylib 0x00007fff6e58c808 abort + 120
3 com.apple.dt.IDEKit 0x0000000108792bc6 +[IDEAssertionHandler
handleAssertionWithLogString:assertionSignature:assertionReason:extraBacktrace:] + 1275
4 com.apple.dt.IDEKit 0x00000001087930cc -[IDEAssertionHandler handleFailureInMethod:object:fileName:lineNumber:assertionSignature:messageFormat:arguments:] + 1068
5 com.apple.dt.DVTFoundation 0x0000000106c2c88d DVTAssertionHandler + 476
6 com.apple.dt.DVTFoundation 0x0000000106c2ca90
DVTAssertionFailureHandler + 306
7 com.apple.dt.DVTFoundation 0x0000000106c4c7c9 _75+[DVTExtendedPlatformInfo extendedPlatformInfoForPlatformIdentifier:error:]blockinvoke + 1511
8 libdispatch.dylib 0x00007fff6e464658
dispatchclientcallout + 8
9 libdispatch.dylib 0x00007fff6e4657de dispatchoncecallout + 20
10 com.apple.dt.DVTFoundation 0x0000000106c4c19e +[DVTExtendedPlatformInfo extendedPlatformInfoForPlatformIdentifier:error:] + 639
11 com.apple.dt.DVTFoundation 0x0000000106c4e20f -[DVTPlatform(DVTExtendedPlatformInfo) dvt
extendedInfoOrError:] + 68
12 com.apple.dt.DVTFoundation 0x0000000106ae5a9d +[DVTPlatform validatePlatformDataReturningError:] + 362
13 com.apple.dt.IDEFoundation 0x00000001076d3ff8 IDEInitialize + 7706
14 com.apple.dt.IDEKit 0x000000010876e5dc -[IDEApplicationController applicationWillFinishLaunching:] + 622
15 com.apple.CoreFoundation 0x00007fff343cc2c9 CFNOTIFICATIONCENTERISCALLINGOUTTOANOBSERVER + 12
16 com.apple.CoreFoundation 0x00007fff343cc25d __CFXRegistrationPost1blockinvoke + 63
17 com.apple.CoreFoundation 0x00007fff343cc1d2
CFXRegistrationPost1 + 372
18 com.apple.CoreFoundation 0x00007fff343cbe3e __CFXNotificationPostblockinvoke + 80
19 com.apple.CoreFoundation 0x00007fff3439c02c -[
CFXNotificationRegistrar find:object:observer:enumerator:] + 1745
20 com.apple.CoreFoundation 0x00007fff3439b3f5 CFXNotificationPost + 1586
21 com.apple.Foundation 0x00007fff36a39786 -[NSNotificationCenter postNotificationName:object:userInfo:] + 59
22 com.apple.dt.DVTFoundation 0x0000000106ac98a0 -[NSNotificationCenter(DVTNSNotificationCenterAdditions
MRR) dvtpostNotificationName:object:userInfo:] + 177
23 com.apple.AppKit 0x00007fff3162a059 -[NSApplication finishLaunching] + 330
24 com.apple.dt.DVTKit 0x0000000107303d88 -[DVTApplication finishLaunching] + 293
25 com.apple.AppKit 0x00007fff31629be0 -[NSApplication run] + 244
26 com.apple.AppKit 0x00007fff315fbb86 NSApplicationMain + 777
27 libdyld.dylib 0x00007fff6e4bdcc9 start + 1
I am now getting this crash since installing Xcode 12 beta 6. I was not getting it in any of the previous betas. It happens on every launch, same assertion failure and callstack as above.
Same problem occurred many times after reinstall Xcode app.

The solution was:
  1. Open a random swift file (eg. AppDelegate.swift)

  2. Open the project.

  3. Clean the build folder (Product->Clean Build Folder)

This method worked for me, I don't know why!
Xcode 12b2 crashes at launch with ASSERTION FAILURE in /Library/Caches/com.apple.xbs/Sources/DVTFrameworks/DVTFrameworks-17160.5/DVTFoundation/DeveloperStructure/DVTExtendedPlatformInfo.m:110
 
 
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