I've just updated to Unity2017 and after building to iOS I am getting the following error:Assertion failed: TLS Allocator ALLOC_TEMP_THREAD, underlying allocator ALLOC_TEMP_THREAD has unfreed allocations

I’ve just updated to Unity2017 and after building to iOS I am getting the following error:Assertion failed: TLS Allocator ALLOC_TEMP_THREAD, underlying allocator ALLOC_TEMP_THREAD has unfreed allocations

The build didn’t seem to fail but in general error messages make me wary. Any idea why this might be happening?

This issue is currently being tracked here: Unity Issue Tracker - "Assertion failed: TLS Allocator ALLOC_TEMP_THREAD..." error is shown after building the project for iOS'

I solved this error. You must change .net option in player setting .net 3.5 to .net 4.6.

I fixed this issue by deleting the following folders in my project:

/Library
/Temp
/UnityPackageManager

I restarted, and the error did not spawn any longer.

Before this, I tried Bilgisoft’s solution which did not help.

Update
Dang, that is, it actually stopped the error as I was running the Windows platform in build settings. Once I switched back to Android, the issue came back.