`System.Text.Json.SourceGeneration.Roslyn3.11.Tests` crashes due to an assertion on linux/arm64/debug

[radical]

Hit this on #65752 .Build.

=================================================================
	Native stacktrace:
=================================================================
	0x7f9518ccbc - Unknown

Unhandled Exception:
System.Diagnostics.DebugProvider+DebugAssertException:    at System.Diagnostics.DebugProvider.Fail(String message, String detailMessage) in /_/src/libraries/System.Private.CoreLib/src/System/Diagnostics/DebugProvider.cs:line 22
   at System.Diagnostics.Debug.Fail(String message, String detailMessage) in /_/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Debug.cs:line 131
   at System.Diagnostics.Debug.Assert(Boolean condition, String message, String detailMessage) in /_/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Debug.cs:line 95
   at System.Diagnostics.Debug.Assert(Boolean condition) in /_/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Debug.cs:line 80
   at System.Text.Json.Serialization.Metadata.JsonTypeInfo.InitializePropCache() in /_/src/libraries/System.Text.Json/src/System/Text/Json/Serialization/Metadata/JsonTypeInfo.Cache.cs:line 574
...

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Issue Details

---

Hit this on #65752 .Build.

=================================================================
	Native stacktrace:
=================================================================
	0x7f9518ccbc - Unknown

Unhandled Exception:
System.Diagnostics.DebugProvider+DebugAssertException:    at System.Diagnostics.DebugProvider.Fail(String message, String detailMessage) in /_/src/libraries/System.Private.CoreLib/src/System/Diagnostics/DebugProvider.cs:line 22
   at System.Diagnostics.Debug.Fail(String message, String detailMessage) in /_/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Debug.cs:line 131
   at System.Diagnostics.Debug.Assert(Boolean condition, String message, String detailMessage) in /_/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Debug.cs:line 95
   at System.Diagnostics.Debug.Assert(Boolean condition) in /_/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Debug.cs:line 80
   at System.Text.Json.Serialization.Metadata.JsonTypeInfo.InitializePropCache() in /_/src/libraries/System.Text.Json/src/System/Text/Json/Serialization/Metadata/JsonTypeInfo.Cache.cs:line 574
...

Author:	radical
Assignees:	-
Labels:	area-System.Text.Json, blocking-clean-ci, untriaged
Milestone:	-

[radical]

Hit this again for System.Text.Json.SourceGeneration.Roslyn4.0.Tests.

[krwq]

Note this is about Debug.Assert(PropertyCache == null); in InitializePropCache

I think this assert is just bogus and should be removed. I assume scenario of re-using same options on multiple threads is a valid one and that could create such problem. The worst case scenario we will double initialize PropertyCache. I'm not sure it makes sense to lock it - at least cannot immediately see anything which could break. Same goes for the similar assert in the InitializeParameterCache

@eiriktsarpalis @layomia?

[eiriktsarpalis]

I think we should make sure that the instance is initialized before it can be shared across multiple threads.