Bug 11773 - Compiler as a service broken in Mono 3.0.9 (osx package)
Summary: Compiler as a service broken in Mono 3.0.9 (osx package)
Alias: None
Product: Compilers
Classification: Mono
Component: C# ()
Version: unspecified
Hardware: PC Mac OS
: --- normal
Target Milestone: ---
Assignee: Marek Safar
Depends on:
Reported: 2013-04-13 21:05 UTC by Jonathan Shore
Modified: 2013-04-14 12:08 UTC (History)
1 user (show)

Is this bug a regression?: ---
Last known good build:

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Description Jonathan Shore 2013-04-13 21:05:10 UTC
I have been trying to uses Mono.CSharp to compile C# code at run time with mono 3.0.9.  I am having problems creating object instances for any class defined without the compiler-as-a-service environment.  This problem is easily reproduced with the C# repl (csharp command line tool):

csharp> class A 
      > {
      >    public string Name { get; set; }
      > }

csharp> new A();

Mono.CSharp.InternalErrorException: (1,1): <InteractiveExpressionClass>.Host(ref object) ---> System.NullReferenceException: Object reference not set to an instance of an object
  at Mono.CSharp.Parameter.ApplyAttributes (System.Reflection.Emit.MethodBuilder mb, System.Reflection.Emit.ConstructorBuilder cb, Int32 index, Mono.CSharp.PredefinedAttributes pa) [0x00000] in <filename unknown>:0 
  at Mono.CSharp.ParametersCompiled.ApplyAttributes (IMemberContext mc, System.Reflection.MethodBase builder) [0x00000] in <filename unknown>:0 
  at Mono.CSharp.MethodData.Emit (Mono.CSharp.TypeDefinition parent) [0x00000] in <filename unknown>:0 
  at Mono.CSharp.MethodOrOperator.Emit () [0x00000] in <filename unknown>:0 
  at Mono.CSharp.Method.Emit () [0x00000] in <filename unknown>:0 
  --- End of inner exception stack trace ---
  at Mono.CSharp.Method.Emit () [0x00000] in <filename unknown>:0 
  at Mono.CSharp.TypeDefinition.Emit () [0x00000] in <filename unknown>:0 
  at Mono.CSharp.ClassOrStruct.Emit () [0x00000] in <filename unknown>:0 
  at Mono.CSharp.Class.Emit () [0x00000] in <filename unknown>:0 
  at Mono.CSharp.TypeDefinition.EmitContainer () [0x00000] in <filename unknown>:0 
  at Mono.CSharp.Evaluator.CompileBlock (Mono.CSharp.Class host, Mono.CSharp.Undo undo, Mono.CSharp.Report Report) [0x00000] in <filename unknown>:0 
  at Mono.CSharp.Evaluator.Compile (System.String input, Mono.CSharp.CompiledMethod& compiled) [0x00000] in <filename unknown>:0 
  at Mono.CSharp.Evaluator.Evaluate (System.String input, System.Object& result, System.Boolean& result_set) [0x00000] in <filename unknown>:0 
  at Mono.CSharpShell.Evaluate (System.String input) [0x00000] in <filename unknown>:0
Comment 1 Marek Safar 2013-04-14 12:08:54 UTC
You need to use Mono 3.0.10. Unfortunately 3.0.9 has broken repl.