DLR - 为啥我的堆栈跟踪中没有显示调试信息？

Posted 2023-02-21

【中文标题】DLR - 为啥我的堆栈跟踪中没有显示调试信息？

【英文标题】：DLR - Why isn't debug information showing up in my stacktrace?DLR - 为什么我的堆栈跟踪中没有显示调试信息？

【发布时间】：2013-03-13 15:50:45

【问题描述】：

首先，我已经阅读了Making a CLR/.NET Language Debuggable，但我仍然无法实现这一点。

我编写了一种玩具语言，它通过生成 Linq 表达式，然后调用 LambdaExpression#CompileToMethod 来工作。这些表达式中的大多数都附加了调试信息，如下所示：

//SmithExpression#InsertDebugInfo
Expression InsertDebugInfo(Expression expression, DebugInfo debugInfo) 
    var column = 1;
    var debugExpr = Expression.DebugInfo(debugInfo.SymbolDocumentInfo
                 ,Info.LineNumber, column, Info.LineNumber, column + 1);
    return Expression.Block(debugExpr, expression);

DebugInfo 如下所示：

public class DebugInfo 
    /* arbitrary value from http://www.famkruithof.net/uuid/uuidgen */
    public static Guid SmithGuid = new Guid("83c65910-8376-11e2-9e96-0800200c9a66");

    public readonly SymbolDocumentInfo SymbolDocumentInfo;
    public readonly DebugInfoGenerator DebugPdbGenerator;

    public DebugInfo(String name) 
        SymbolDocumentInfo = Expression.SymbolDocument(name, SmithGuid);
        DebugPdbGenerator = DebugInfoGenerator.CreatePdbGenerator();
    

整个事情是这样编译的（你可以忽略关于init的部分）：

public static Action CompileSmithExpression(SmithExpression sexpression
           ,DebugInfo debugInfo, Parameter moduleParameter, Expando module) 
    AssemblyName assemblyName = 
        new AssemblyName(
             "RuntimeHelpers.CompileToSmithExpression helper assembly"
          );
    AssemblyBuilder assemblyBuilder =
        AppDomain.CurrentDomain.DefineDynamicAssembly(
          assemblyName, AssemblyBuilderAccess.RunAndSave
        );

    ModuleBuilder moduleBuilder = assemblyBuilder
             .DefineDynamicModule(assemblyName.Name, "onlyModule.dll");

    var debugAttributes =
        DebuggableAttribute.DebuggingModes.Default |
        DebuggableAttribute.DebuggingModes.DisableOptimizations;

    ConstructorInfo constructor =
        typeof(DebuggableAttribute)
       .GetConstructor(new Type[]  
           typeof(DebuggableAttribute.DebuggingModes)
           
        );
    var cab = new CustomAttributeBuilder(constructor, new object[]  debugAttributes );
    assemblyBuilder.SetCustomAttribute(cab);
    moduleBuilder.SetCustomAttribute(cab);

    TypeBuilder typeBuilder = 
       moduleBuilder.DefineType("MyDynamicType", TypeAttributes.Public);

    //inits generates expressions that set 'constant' fields to their values.
    //the call also adds the 'constant' fields to the typeBuilder.
    //Must call ToArray() to make it run.
    var inits = FieldInits(sexpression, typeBuilder).ToArray();
    var ex = sexpression.ToExpression(debugInfo);
    var fullDlrExpression = Expression.Block(inits.Append(ex));

    var parameters = new ParameterExpression[]  moduleParameter.DlrParameter ;
    var lambda = Expression.Lambda(fullDlrExpression, parameters);

    /* Method will take the module as a parameter. */
    MethodBuilder meth = typeBuilder.DefineMethod(
        "MyMethod",
        MethodAttributes.Public | MethodAttributes.Static,
        typeof(void),
        new Type[]  typeof(Expando)  );

    lambda.CompileToMethod(meth, debugInfo.DebugPdbGenerator);

    Type madeType = typeBuilder.CreateType();

    return () => madeType.GetMethod("MyMethod").Invoke(null, new Object[]  module );

运行代码给出了我想要的异常，但不包括表达式所具有的调试信息。我希望它说“”之类的内容。

Unhandled Exception: System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.MissingMemberException: Can't invoke member error of [] []
at (wrapper dynamic-method) object.CallSite.Target (System.Runtime.CompilerServices.Closure,System.Runtime.CompilerServices.CallSite,Smith.Expando) <IL 0x0004f, 0x00127>
at System.Dynamic.UpdateDelegates.UpdateAndExecute1<Smith.Expando, object> (System.Runtime.CompilerServices.CallSite,Smith.Expando) <0x0040b>
at MyDynamicType.MyMethod (Smith.Expando) <IL 0x002bc, 0x00aaa>
at (wrapper managed-to-native) System.Reflection.MonoMethod.InternalInvoke (System.Reflection.MonoMethod,object,object[],System.Exception&) <IL 0x00016, 0x00067>
etc...

我最好的猜测是调试信息确实在那里，但我必须做更多的工作才能让堆栈跟踪显示它。有什么想法吗？

【问题讨论】：

肯定更多的工作，没有什么简单的。 dlr.codeplex.com/discussions/80850

"IronRuby 通过在编译时提供 DebugInfoGenerator 来维护 IL 偏移到行号的映射。"这正是我想要做的，并且每个表达式都已经用 DebugInfoExpression 进行了标记。如果有办法从 IL 位置到离它最近的 DebugInfoExpression 行号，那么我可以进行堆栈跟踪。

【参考方案1】：

您的异常是嵌套异常。要打印堆栈跟踪，请查看 InnerException。

catch (Exception ex)

    while (ex != null) 
        Debug.Print(ex.ToString());
        ex = ex.InnerException();