Debug disassembled code

1. Right-click the desired frame in the Debug tool window and select Disassemble:

   

2. Disassembly view will be opened side-by-side with the source code:

   

   Once opened, the disassembly view stays synchronized with the currently selected frame. When frames are switched, both the editor and the disassembly view scroll to the execution point.

   note

   All the debug actions described below are available in this side-by-side view, with an exception that currently CLion does not mirror breakpoints between the source file and the disassembly view.

• When debugging your code, use the Force Step Into AltShiftF7 command instead of Step Into F7. Step Into acts like Step Over for functions with no source code.

  Disassembly view opens automatically when CLion cannot locate the source files during debugging. This can happen, for example, when you debug a custom executable using a fake CMake project or when there is a library built on CI without the source code being in the project.

  To explicitly specify the source, click Select file in the notification:

  

• Navigate to the desired frame in the Debug tool window.

• Disassembly also opens automatically when you launch a debug session for the attached process that does not provide debug information.

While in disassembly view, you can investigate your code using regular stepping actions.

tip

Stepping in disassembly and in the original sources behaves differently: although debugger always steps line-by-line, a line in the source code usually contains multiple instructions, while a line in disassembly always corresponds to a single instruction.

Gif

You can also use the Set Execution Point action to jump to an arbitrary line of code in disassembly:

You can set breakpoints in disassembly the same way you do in the source code. These breakpoints are called address breakpoints.

Right-click a breakpoint to view the available options:

Click More or press CtrlShiftF8 to edit address breakpoints in the Breakpoints dialog:

note

When you stop a debug session, address breakpoints are removed automatically, because most of the time the address layout changes on the next launch. This behavior is similar to watchpoints.

Use the Go to field to jump to a desired code line. In this field, you can enter an address or any expression that can be evaluated into an address.

If you need to include a register into the expression, start its name with $ (the GDB notation).

tip

Using registers in the Go to field while debugging with LLDB requires explicit cast to address. For example, (void *)($pc + 0x8).

• Use the menu to switch to x86 assembly (Intel) syntax:

  

  This option is also available in Assembly view for files. The configurations are independent: the Disassembly view configuration does not affect the Assembly view, and vice versa.

  note

  The Use Intel Syntax option is disabled for ARM architectures and MSVC toolchains.

Syntax highlighting is available for AT&T assembly code.

By default, the .s and .asm files are recognized as assembly code files, but you can configure other types:

1. Go to Settings | Editor | File Types.

2. Select Assembly Language in the list of recognized file types and add a new extension to the list.