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DebuggableAttribute.DebuggingModes Enumeration

Specifies the debugging mode for the just-in-time (JIT) compiler.

This enumeration has a FlagsAttribute attribute that allows a bitwise combination of its member values.

Namespace:  System.Diagnostics
Assembly:  mscorlib (in mscorlib.dll)

public enum DebuggingModes

Member nameDescription
Supported by the .NET Compact FrameworkSupported by the XNA FrameworkNoneIn the .NET Framework version 2.0, JIT tracking information is always generated, and this flag has the same effect as Default with the exception of the IsJITTrackingEnabled property being false, which has no meaning in version 2.0.
Supported by the .NET Compact FrameworkSupported by the XNA FrameworkDefaultInstructs the just-in-time (JIT) compiler to use its default behavior, which includes enabling optimizations, disabling Edit and Continue support, and using symbol store sequence points if present. In the .NET Framework version 2.0, JIT tracking information, the Microsoft intermediate language (MSIL) offset to the native-code offset within a method, is always generated.
Supported by the .NET Compact FrameworkSupported by the XNA FrameworkDisableOptimizationsDisable optimizations performed by the compiler to make your output file smaller, faster, and more efficient. Optimizations result in code rearrangement in the output file, which can make debugging difficult. Typically optimization should be disabled while debugging.
Supported by the .NET Compact FrameworkSupported by the XNA FrameworkIgnoreSymbolStoreSequencePointsUse the implicit MSIL sequence points, not the program database (PDB) sequence points. The symbolic information normally includes at least one Microsoft intermediate language (MSIL) offset for each source line. When the just-in-time (JIT) compiler is about to compile a method, it asks the profiling services for a list of MSIL offsets that should be preserved. These MSIL offsets are called sequence points.
Supported by the .NET Compact FrameworkSupported by the XNA FrameworkEnableEditAndContinueEnable edit and continue. Edit and continue enables you to make changes to your source code while your program is in break mode. The ability to edit and continue is compiler dependent.

The DebuggableAttribute.DebuggingModes enumeration specifies how the runtime is to track information important to the debugger during code generation. This information helps the debugger provide a rich debugging experience. In the .NET Framework version 2.0, calling the DebuggableAttribute(DebuggableAttribute.DebuggingModes) constructor with a modes parameter value of Default is equivalent to calling the DebuggableAttribute(Boolean, Boolean) constructor with an isJITTrackingEnabled parameter value of true in the .NET Framework version 1.1. Unlike version 1.1, version 2.0 does not allow you to turn off tracking by the just-in-time (JIT) compiler. JIT tracking is always enabled for debuggable files.

Sequence points are used to indicate locations in the Microsoft intermediate language (MSIL) code that a debugger user will expect to be able to refer to uniquely, such as for setting a breakpoint. The JIT compiler ensures it does not compile the MSIL at two different sequence points into a single native instruction. By default, the JIT compiler examines the symbol store in the program database (PDB) file for a list of additional sequence points. However, loading the PDB file requires that the file be available and has a negative performance impact. In version 2.0, compilers can emit "implicit sequence points" in the MSIL code stream through the use of MSIL "nop" instructions. Such compilers should set the IgnoreSymbolStoreSequencePoints flag to notify the common language runtime to not load the PDB file.


This enumeration is primarily used by language developers. It is generally not used in application development. Development environments use DebuggableAttribute.DebuggingModes based on compiler parameters such as /debug and /optimize.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0

.NET Compact Framework

Supported in: 3.5, 2.0

XNA Framework

Supported in: 3.0, 2.0, 1.0