System.IO.FileLoadException: Could not load file or assembly 'System.Runtime.CompilerServices.Unsafe, Version=4.0.4.1

[carstenh123]

Hi,

I am using Microsoft.CodeDom.Providers.DotNetCompilerPlatform.dll version 4.1.0 in my web service project that is .net48 based.

After i have deployed my web service i get this file load exception in the event viewer when accessing the web service:

Faulting application name: csc.exe, version: 4.100.22.11411, time stamp: 0xb38fc9ae
Faulting module name: KERNELBASE.dll, version: 10.0.17763.2028, time stamp: 0x4569c786
Exception code: 0xe0434352
Fault offset: 0x0000000000039329
Faulting process id: 0x2dd4
Faulting application start time: 0x01dca6365e0cb0da
Faulting application path: C:\xyz\xyz\bin\roslyn\csc.exe
Faulting module path: C:\Windows\System32\KERNELBASE.dll
Report Id: 2eaf6326-bd27-47a2-aec3-ae9001aa314c
Faulting package full name:
Faulting package-relative application ID:

and:

Application: csc.exe
Framework Version: v4.0.30319
Description: The process was terminated due to an unhandled exception.
Exception Info: System.IO.FileLoadException
at System.MemoryExtensions.AsSpan(System.String)
at Roslyn.Utilities.CommandLineUtilities.SplitCommandLineIntoArguments(System.String, Boolean, System.Nullable1<Char> ByRef) at Microsoft.CodeAnalysis.CommandLine.BuildClient.GetCommandLineWindows(System.Collections.Generic.IEnumerable1<System.String>)
at Microsoft.CodeAnalysis.CommandLine.BuildClient.Run(System.Collections.Generic.IEnumerable`1<System.String>, Microsoft.CodeAnalysis.CommandLine.RequestLanguage, Microsoft.CodeAnalysis.CommandLine.CompileFunc, Microsoft.CodeAnalysis.CommandLine.CompileOnServerFunc)
at Microsoft.CodeAnalysis.CSharp.CommandLine.Program.MainCore(System.String[])
at Microsoft.CodeAnalysis.CSharp.CommandLine.Program.Main(System.String[])

When i try to run the csc.exe as admin in a command prompt i get:
PS C:\xyz\xyz\bin\roslyn> .\csc.exe

Unhandled Exception: System.IO.FileLoadException: Could not load file or assembly 'System.Runtime.CompilerServices.Unsafe, Version=4.0.4.1, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
at System.MemoryExtensions.AsSpan(String text)
at Roslyn.Utilities.CommandLineUtilities.SplitCommandLineIntoArguments(String commandLine, Boolean removeHashComments, Nullable1& illegalChar) at Microsoft.CodeAnalysis.CommandLine.BuildClient.GetCommandLineWindows(IEnumerable1 args)
at Microsoft.CodeAnalysis.CommandLine.BuildClient.Run(IEnumerable`1 arguments, RequestLanguage language, CompileFunc compileFunc, CompileOnServerFunc compileOnServerFunc)
at Microsoft.CodeAnalysis.CSharp.CommandLine.Program.MainCore(String[] args)
at Microsoft.CodeAnalysis.CSharp.CommandLine.Program.Main(String[] args)

The provided System.Runtime.CompilerServices.Unsafe.dll in the bin\roslyn folder is version 5.0.20.51904.

I wonder why System.Runtime.CompilerServices.Unsafe.dll is not version 4.0.4.1.

Have any one else seen this issue or can help me fixing it?

Thanks in advance
C.