Repro steps:
1) Open attached project (BadAttribute.zip)
2) Unity crashes

Reproduces on:
2020.2.0b2, 2020.3.0f1
2021.1.0b6
2021.2.0a1, 2021.2.0a9

The problem is that if mono_custom_attrs_construct() is called with an attribute type that throws an exception in its constructor, then unity crashes.

Callstack:
2021-03-12T15:35:34.272Z|0x8f80|0x00007FF9BA194E18 (mono-2.0-bdwgc) (function-name not available)
2021-03-12T15:35:34.272Z|0x8f80|0x00007FF9BA1AB7EA (mono-2.0-bdwgc) mono_property_hash_remove_object
2021-03-12T15:35:34.272Z|0x8f80|0x00007FF9BA2A82B1 (mono-2.0-bdwgc) mono_custom_attrs_construct
2021-03-12T15:35:34.803Z|0x8f80|0x00007FF62C15FFF1 (Unity) [D:\repos\unity\dev13\Runtime\ScriptingBackend\Mono\ScriptingApi_Mono.cpp:900] scripting_custom_attrs_construct
2021-03-12T15:35:34.805Z|0x8f80|0x00007FF62C0DD1A8 (Unity) [D:\repos\unity\dev13\Runtime\Scripting\AttributeScanner.cpp:43] AttributeCollectionInfo::AllocAttributesArrayIfNeeded
2021-03-12T15:35:34.806Z|0x8f80|0x00007FF62C0E7508 (Unity) [D:\repos\unity\dev13\Runtime\Scripting\AttributeScanner.cpp:59] AttributeCollectionInfo::GetAttributeObjectsArrayCount
2021-03-12T15:35:34.806Z|0x8f80|0x00007FF62C0EC534 (Unity) [D:\repos\unity\dev13\Runtime\Scripting\ManagedAttributeManager.cpp:476] ManagedAttributeManager::GetRequiredComponents
2021-03-12T15:35:34.808Z|0x8f80|0x00007FF62C0B4A31 (Unity) [D:\repos\unity\dev13\Runtime\Mono\MonoBehaviour.cpp:1665] RequiredComponentsOf
2021-03-12T15:35:34.809Z|0x8f80|0x00007FF62AD59CCE (Unity) [D:\repos\unity\dev13\Runtime\Misc\GameObjectUtility.cpp:603] CollectRequiredScriptComponents
2021-03-12T15:35:34.809Z|0x8f80|0x00007FF62AD59BA6 (Unity) [D:\repos\unity\dev13\Runtime\Misc\GameObjectUtility.cpp:909] CollectRequiredComponentsWithoutAdding
2021-03-12T15:35:34.809Z|0x8f80|0x00007FF62AD591E3 (Unity) [D:\repos\unity\dev13\Runtime\Misc\GameObjectUtility.cpp:929] CollectComponentsWithoutAdding
2021-03-12T15:35:34.810Z|0x8f80|0x00007FF62AD5300A (Unity) [D:\repos\unity\dev13\Runtime\Misc\GameObjectUtility.cpp:946] AddComponent
2021-03-12T15:35:34.810Z|0x8f80|0x00007FF62AD52B6E (Unity) [D:\repos\unity\dev13\Runtime\Misc\GameObjectUtility.cpp:1006] AddComponent
2021-03-12T15:35:34.810Z|0x8f80|0x00007FF62AD54234 (Unity) [D:\repos\unity\dev13\Runtime\Misc\GameObjectUtility.cpp:1190] AddMissingComponents
2021-03-12T15:35:34.812Z|0x8f80|0x00007FF62C4809A2 (Unity) [D:\repos\unity\dev13\Runtime\Serialize\AwakeFromLoadQueue.cpp:172] AwakeFromLoadQueue::AddMissingComponents
2021-03-12T15:35:34.812Z|0x8f80|0x00007FF62C48F742 (Unity) [D:\repos\unity\dev13\Runtime\Serialize\AwakeFromLoadQueue.cpp:190] AwakeFromLoadQueue::PersistentManagerAwakeFromLoad
2021-03-12T15:35:34.814Z|0x8f80|0x00007FF62F40124F (Unity) [D:\repos\unity\dev13\Editor\Src\AssetPipeline\PrefabImporter.cpp:399] PrefabImporter::GenerateAssetData
2021-03-12T15:35:34.815Z|0x8f80|0x00007FF6317504D6 (Unity) [D:\repos\unity\dev13\Modules\AssetDatabase\Editor\V2\ImportAsset.cpp:400] PerformImport
2021-03-12T15:35:34.815Z|0x8f80|0x00007FF63174A8EA (Unity) [D:\repos\unity\dev13\Modules\AssetDatabase\Editor\V2\ImportAsset.cpp:884] ImportToObjects
2021-03-12T15:35:34.815Z|0x8f80|0x00007FF631748BCD (Unity) [D:\repos\unity\dev13\Modules\AssetDatabase\Editor\V2\ImportAsset.cpp:991] ImportAsset
2021-03-12T15:35:34.817Z|0x8f80|0x00007FF63157DB72 (Unity) [D:\repos\unity\dev13\Modules\AssetDatabase\Editor\V2\AssetImportWorker.cpp:48] AssetImportWorker::Import
2021-03-12T15:35:34.819Z|0x8f80|0x00007FF63153AC1B (Unity) [D:\repos\unity\dev13\Modules\AssetDatabase\Editor\V2\AssetImportManager.cpp:611] AssetImportManager::ImportInProcess
2021-03-12T15:35:34.819Z|0x8f80|0x00007FF631539976 (Unity) [D:\repos\unity\dev13\Modules\AssetDatabase\Editor\V2\AssetImportManager.cpp:436] AssetImportManager::Import
2021-03-12T15:35:34.822Z|0x8f80|0x00007FF6316C0FE2 (Unity) [D:\repos\unity\dev13\Modules\AssetDatabase\Editor\V2\AssetDatabaseInternal.cpp:3772] ImportAndPostprocessOutOfDateAssets
2021-03-12T15:35:34.823Z|0x8f80|0x00007FF6316DAA4F (Unity) [D:\repos\unity\dev13\Modules\AssetDatabase\Editor\V2\AssetDatabaseInternal.cpp:4625] RefreshInternalV2
2021-03-12T15:35:34.823Z|0x8f80|0x00007FF6316F612D (Unity) [D:\repos\unity\dev13\Modules\AssetDatabase\Editor\V2\AssetDatabaseInternal.cpp:2042] StopAssetImportingV2Internal
2021-03-12T15:35:34.823Z|0x8f80|0x00007FF6316DC5B3 (Unity) [D:\repos\unity\dev13\Modules\AssetDatabase\Editor\V2\AssetDatabaseInternal.cpp:4797] RefreshV2
2021-03-12T15:35:34.825Z|0x8f80|0x00007FF6314D44C2 (Unity) [D:\repos\unity\dev13\Modules\AssetDatabase\Editor\Public\AssetDatabase.cpp:398] AssetDatabase::Refresh
2021-03-12T15:35:34.828Z|0x8f80|0x00007FF62F35F3B6 (Unity) [D:\repos\unity\dev13\Editor\Src\Application\Application.cpp:1354] Application::InitializeProject
2021-03-12T15:35:34.829Z|0x8f80|0x00007FF63083950D (Unity) [D:\repos\unity\dev13\Editor\Platform\Windows\WinEditorMain.cpp:1017] WinMain
2021-03-12T15:35:34.829Z|0x8f80|0x00007FF6352A9D82 (Unity) [d:\agent\_work\63\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:107] invoke_main
2021-03-12T15:35:34.829Z|0x8f80|0x00007FF6352A9C6E (Unity) [d:\agent\_work\63\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288] __scrt_common_main_seh
2021-03-12T15:35:34.829Z|0x8f80|0x00007FF6352A9B2E (Unity) [d:\agent\_work\63\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:331] __scrt_common_main
2021-03-12T15:35:34.830Z|0x8f80|0x00007FF6352A9E19 (Unity) [d:\agent\_work\63\s\src\vctools\crt\vcstartup\src\startup\exe_winmain.cpp:17] WinMainCRTStartup
2021-03-12T15:35:34.830Z|0x8f80|0x00007FFA6C147034 (KERNEL32) BaseThreadInitThunk
2021-03-12T15:35:34.830Z|0x8f80|0x00007FFA6DFC2651 (ntdll) RtlUserThreadStart