Bug 7826 - Internal error compiling async method.
Summary: Internal error compiling async method.
Status: RESOLVED FIXED
Alias: None
Product: Compilers
Classification: Mono
Component: C# ()
Version: unspecified
Hardware: PC Windows
: --- normal
Target Milestone: ---
Assignee: Marek Safar
URL:
Depends on:
Blocks:
 
Reported: 2012-10-13 12:22 UTC by Erik Källén
Modified: 2012-10-16 06:53 UTC (History)
2 users (show)

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

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Status:
RESOLVED FIXED

Description Erik Källén 2012-10-13 12:22:58 UTC
Compiling the following file with mcs 2.11.4 gives an internal error:

using System;
using System.Threading.Tasks;

class Program {
	public class C {
		public void M() {}
	}

	public static void F(Action<C> a) {
	}

	public static void Main() {
		F(async (c) => {
			await Task.Run(() => {});
			c.M();
		});
	}
}


Error details:

System.NullReferenceException: Object reference not set to an instance of an object
  at Mono.CSharp.FieldExpr..ctor (Mono.CSharp.FieldSpec spec, Location loc) [0x00000] in <filename unknown>:0
  at Mono.CSharp.FieldExpr..ctor (Mono.CSharp.FieldBase fi, Location l) [0x00000] in <filename unknown>:0
  at Mono.CSharp.AnonymousMethodStorey.EmitHoistedParameters (Mono.CSharp.EmitContext ec, System.Collections.Generic.List`1 hoisted) [0x00000] in <filename unknown>:0
  at Mono.CSharp.AnonymousMethodStorey.EmitHoistedFieldsInitialization (Mono.CSharp.ResolveContext rc, Mono.CSharp.EmitContext ec) [0x00000] in <filename unknown>:0
  at Mono.CSharp.AnonymousMethodStorey.EmitStoreyInstantiation (Mono.CSharp.EmitContext ec, Mono.CSharp.ExplicitBlock block) [0x00000] in <filename unknown>:0
  at Mono.CSharp.ParametersBlock.Emit (Mono.CSharp.EmitContext ec) [0x00000] in
<filename unknown>:0
  at Mono.CSharp.ToplevelBlock.Emit (Mono.CSharp.EmitContext ec) [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
[ERROR] FATAL UNHANDLED EXCEPTION: System.NullReferenceException: Object reference not set to an instance of an object
  at Mono.CSharp.FieldExpr..ctor (Mono.CSharp.FieldSpec spec, Location loc) [0x00000] in <filename unknown>:0
  at Mono.CSharp.FieldExpr..ctor (Mono.CSharp.FieldBase fi, Location l) [0x00000] in <filename unknown>:0
  at Mono.CSharp.AnonymousMethodStorey.EmitHoistedParameters (Mono.CSharp.EmitContext ec, System.Collections.Generic.List`1 hoisted) [0x00000] in <filename unknown>:0
  at Mono.CSharp.AnonymousMethodStorey.EmitHoistedFieldsInitialization (Mono.CSharp.ResolveContext rc, Mono.CSharp.EmitContext ec) [0x00000] in <filename unknown>:0
  at Mono.CSharp.AnonymousMethodStorey.EmitStoreyInstantiation (Mono.CSharp.EmitContext ec, Mono.CSharp.ExplicitBlock block) [0x00000] in <filename unknown>:0
  at Mono.CSharp.ParametersBlock.Emit (Mono.CSharp.EmitContext ec) [0x00000] in
<filename unknown>:0
  at Mono.CSharp.ToplevelBlock.Emit (Mono.CSharp.EmitContext ec) [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
Comment 1 Marek Safar 2012-10-16 06:53:41 UTC
Fixed in master