Steps to reproduce:
1. Open user-supplied project
2. Enter Play mode

Expected: no errors in the Console window
Actual: errors appear in the Console window

Reproduced in: 2019.1.10f1, 2019.2.0b10, 2019.3.0a10
Not reproduced in: 2017.4.30f1*, 2018.4.5f1*

Full error:
*Can't run due to compile errors

\...\Assets\MemoryBlock.cs(128,17): error: Unexpected error while processing instruction `IL_0021: ldsfld Containers.Unsafe.NativeSlice`1<T> MemoryUtils.Unsafe.MemoryBlock`1<T>::NULL`. Reason: Object reference not set to an instance of an object
at MemoryUtils.Unsafe.MemoryBlock`1<System.Int32>.GetData(MemoryUtils.Unsafe.MemoryBlock`1<int>* this, ref int size, ref Containers.Unsafe.NativeSlice`1<int> slice) (at D:\Downloads\case_1170768-burst_block\Assets\MemoryBlock.cs:128)
at Test.BJob.Execute(Test.BJob* this) (at D:\Downloads\case_1170768-burst_block\Assets\Test.cs:19)
at Unity.Jobs.IJobExtensions.JobStruct`1<Test.BJob>.Execute(ref Test.BJob data, System.IntPtr additionalPtr, System.IntPtr bufferRangePatchData, ref Unity.Jobs.LowLevel.Unsafe.JobRanges ranges, int jobIndex)

Internal compiler exception: System.NullReferenceException: Object reference not set to an instance of an object
at Burst.Compiler.IL.ILCompiler.Ldsfld (Burst.Compiler.IL.Syntax.ILInstruction inst) [0x00067] in <2c9ff9fb581642acaeb86844246ad423>:0
at Burst.Compiler.IL.ILCompiler.CompileInternal (Burst.Compiler.IL.Syntax.ILInstruction inst) [0x004f4] in <2c9ff9fb581642acaeb86844246ad423>:0
at Burst.Compiler.IL.ILCompiler.Compile (Burst.Compiler.IL.Syntax.ILInstruction inst) [0x00030] in <2c9ff9fb581642acaeb86844246ad423>:0
at Burst.Compiler.IL.ILCompiler.VisitImpl (Burst.Compiler.IL.Syntax.ILInstruction inst) [0x00066] in <2c9ff9fb581642acaeb86844246ad423>:0
at Burst.Compiler.IL.ILVisitor.Visit (Burst.Compiler.IL.Syntax.ILInstruction instruction) [0x00007] in <2c9ff9fb581642acaeb86844246ad423>:0

While compiling job: System.Void Unity.Jobs.IJobExtensions/JobStruct`1<Test/BJob>::Execute(T&,System.IntPtr,System.IntPtr,Unity.Jobs.LowLevel.Unsafe.JobRanges&,System.Int32)