Added wrap-up GSoC presentation and blog (#344)

* Added wrap-up gsoc presentation and blog

* Updated spellings

Author: kr-2003

.github/actions/spelling/allow/terms.txt

@@ -62,6 +62,7 @@ gridlay
 gsoc
 hpc
 jit
+jitlink
 jthread
 linkedin
 llm
@@ -70,6 +71,7 @@ meetinglist
 microenvironments
 omp
 openmp
+oop
 pushforward
 pythonized
 ramview
@@ -84,6 +86,7 @@ softsusy
 superbuilds
 tapenade
 vimeo
+watchpoints
 www
 xcolors
 xcpp

_data/crconlist2025.yml

@@ -23,7 +23,7 @@
         the Out-of-Process JIT execution which was the major part in implementing 
         the debugger. 
 
-      # slides: /assets/presentations/...
+      slides: /assets/presentations/Abhinav_Kumar_GSoC25_final.pdf
 
     - title: "Activity analysis for reverse-mode differentiation of (CUDA) GPU kernels"
       speaker:

_data/standing_meetings.yml

@@ -3,6 +3,10 @@
   time_cest: "17:00"
   connect: "[Link to zoom](https://princeton.zoom.us/j/97915651167?pwd=MXJ1T2lhc3Z5QWlYbUFnMTZYQlNRdz09)"
   agenda:
+    - title: "Wrap-Up: Implementing Debugging Support for xeus-cpp"
+      date: 2025-11-13 15:00:00 +0200
+      speaker: "Abhinav Kumar"
+      link: "[Slides](/assets/presentations/Abhinav_Kumar_GSoC25_final.pdf)"
       - title: "Summary: Activity analysis for reverse-mode differentiation of (CUDA) GPU kernels"
       date: 2025-11-13 15:30:00 +0200
       speaker: "Maksym Andriichuk"

_posts/2025-11-14-implement-debugging-support-for-xeus-cpp.md

@@ -0,0 +1,127 @@
+---
+title: "Implementing Debugging Support for xeus-cpp"
+layout: post
+excerpt: "A GSoC 2025 project aiming at integration of debugger into the xeus-cpp kernel for Jupyter using LLDB and its Debug Adapter Protocol (lldb-dap)."
+sitemap: true
+author: Abhinav Kumar
+permalink: blogs/gsoc25_abhinav_kumar_final_blog/
+banner_image: /images/blog/gsoc-banner.png
+date: 2025-11-14
+tags: gsoc c++ debugger dap clang jupyter clang clang-repl
+---
+
+## Introduction
+Hello! I’m Abhinav Kumar, and this summer I had the exciting opportunity to participate in Google Summer of Code (GSoC) 2025. My project revolved around implementing debugging support for xeus-cpp kernel. 
+
+## Project Overview
+`xeus-cpp` is a C++ Jupyter kernel that enables interactive C++ execution within JupyterLab.  
+My project focused on integrating a full-fledged **debugger** into the `xeus-cpp` kernel, enabling users to perform interactive debugging directly from JupyterLab.
+
+The debugger integration is powered by **LLDB-DAP** - the Debug Adapter Protocol implementation for the LLDB debugger. However, directly attaching LLDB-DAP to the kernel process causes the kernel to pause and terminate.  
+To address this, the project leverages **out-of-process JIT execution**, inspired by [Clang-Repl’s Out-of-Process Execution model](https://compiler-research.org/blogs/gsoc24_sahil_wrapup_blog/).
+
+With this design, users can now seamlessly:
+- Set and hit breakpoints  
+- Inspect variables  
+- Step through code (step in, step out, continue)  
+- Debug C++ programs interactively  
+
+all within **JupyterLab**, using the `xeus-cpp` kernel.
+
+## Overview of the Work Done
+
+### JupyterLab
+#### **Pull Request**: [Fix threadId being passed to the debugger #17667](https://github.com/jupyterlab/jupyterlab/pull/17667)
+Identified and fixed a bug in JupyterLab’s frontend debugger implementation.  
+Previously, the [`DebuggerService::_currentThread`](https://github.com/jupyterlab/jupyterlab/blob/72410ce1ac956d4da1769b428de369e84e0b6c17/packages/debugger/src/service.ts#L754) method returned a hardcoded value of `1`.  
+This was corrected to dynamically return the first available `threadId`, ensuring accurate thread handling during debugging sessions.
+
+#### **Issue**: [Bug: Multiple configurationDone Requests Sent by JupyterLab #17673](https://github.com/jupyterlab/jupyterlab/issues/17673)
+Discovered that JupyterLab was sending a `configurationDone` request after every `setBreakpoints` call.  
+According to the Debug Adapter Protocol (DAP) specification, this request should only be sent **once**, after all initial configuration is complete.  
+This issue was reported and documented for further upstream resolution.
+
+---
+
+### CppInterOp
+#### **Pull Request**: [Documentation for debugging CppInterOp using LLDB #621](https://github.com/compiler-research/CppInterOp/pull/621)
+Added comprehensive documentation describing how to debug **CppInterOp** using **LLDB**, making it easier for developers to inspect and troubleshoot CppInterOp internals.
+
+#### **Pull Request**: [Out-Of-Process Interpreter for CppInterOp #717](https://github.com/compiler-research/CppInterOp/pull/717)
+Implemented an **Out-of-Process Interpreter** for CppInterOp.  
+This enhancement utilizes LLVM’s `llvm-jitlink-executor` and the **ORC Runtime** to delegate JIT execution to a separate process.  
+Users can enable this functionality simply by passing the `--use-oop-jit` flag as a `ClangArg` when constructing the interpreter.
+
+---
+
+### LLVM Project
+#### **Pull Request**: [[clang-repl] Adds custom lambda in launchExecutor and PID retrieval](https://github.com/llvm/llvm-project/pull/152562) *(Merged but later reverted by [#153180](https://github.com/llvm/llvm-project/pull/153180))*
+Introduced:
+1. A **custom lambda function** in `launchExecutor`.  
+2. Support for **retrieving the PID** of the launched out-of-process (OOP) JIT executor.  
+
+However, due to issues with the testing infrastructure, the PR was reverted.
+
+#### **Subsequent Pull Requests**
+- [[clang-repl] Sink RemoteJITUtils into Interpreter class (NFC) #155140](https://github.com/llvm/llvm-project/pull/155140)  
+- [[clang-repl] Add support for running custom code in Remote JIT executor #157358](https://github.com/llvm/llvm-project/pull/157358)  
+- [[clang-repl] Disable out of process JIT tests on non-unix platforms #159404](https://github.com/llvm/llvm-project/pull/159404)  
+
+These follow-up PRs addressed the functionality of the reverted change by:
+1. **Refactoring `RemoteJITUtils`**, creating the `JitBuilder` inside the `Interpreter` class.  
+2. **Adding support for custom lambdas** in `launchExecutor`.  
+3. **Enabling PID retrieval** for the launched OOP JIT executor.  
+4. **Improving test reliability** by disabling OOP JIT tests on non-Unix platforms.
+
+---
+
+### **xeus-cpp**
+> The changes in *xeus-cpp* are currently awaiting review and merge.  
+
+#### **Pull Request:** [Debugger for xeus-cpp with testing framework #401](https://github.com/compiler-research/xeus-cpp/pull/401)
+
+This pull request introduces comprehensive debugger support for the *xeus-cpp* kernel.  
+
+**Key contributions include:**
+1. A new kernel variant with an out-of-process interpreter and integrated debugger support.  
+2. Integration of LLDB-DAP within the *xeus* environment.  
+3. A dedicated testing framework to validate and ensure the reliability of debugger functionality.  
+
+## Demo
+### Docker Image
+The provided Docker image is based on **Ubuntu 22.04 (x86_64)**. You can run it on any x86_64 host machine.  
+When launched, it automatically starts a **JupyterLab** instance configured with the **xcpp17-debugger** kernel, allowing you to experiment with the debugger directly.
+
+#### **Commands to Run**
+```bash
+docker pull kr2003/xcpp-debugger
+```
+```bash
+docker run -it --privileged -p 8888:8888 kr2003/xcpp-debugger
+```
+
+Once the container starts, open `localhost:8888` in your browser to access JupyterLab and try out the debugger.
+
+### Video Demo
+[Video demo of xeus-cpp debugger](https://drive.google.com/file/d/1pQZk4OESNQe43LOa4IzZLS1-XfUvXE8e/view?usp=sharing)
+
+## Future Works
+1. **Merge the xeus-cpp debugger support:** Finalize and merge the pending PR by breaking it into 2–3 incremental PRs for better review and integration.  
+2. **Explore LLDB in WebAssembly:** Investigate the feasibility of running LLDB in WASM and adding debugger (DAP) support in JupyterLite.  
+3. **Enhance LLDB-DAP for advanced C++ debugging:** Extend DAP functionality to include advanced C++ debugging features such as watchpoints and data breakpoints.  
+4. **Optimize the out-of-process interpreter:** Improve performance by leveraging shared memory for communication between processes.  
+5. **Expand architecture support:** Extend the out-of-process interpreter to additional architectures beyond Linux x86_64 and macOS Darwin.  
+
+I look forward to continuing contributions beyond GSoC, particularly towards implementing new features and improvements in **clang-repl** and **CppInterOp**.
+
+## Conclusion
+Participating in Google Summer of Code 2025 has been an incredibly enriching experience.  
+Throughout the program, I gained a deeper understanding of how interactive execution, debugging, and JIT compilation work together within the LLVM and Jupyter ecosystems.  
+
+This project not only strengthened my skills in **systems programming**, **compiler internals**, and **debugger integration**, but also gave me the opportunity to collaborate with an inspiring community of developers and mentors at **CERN-HSF**.  
+
+I’m grateful to my mentors — **Anutosh Bhat**, **Vipul Cariappa**, and **Vassil Vassilev** — for their constant support, insightful reviews, and guidance throughout the project.  
+
+While the foundation for debugger support in `xeus-cpp` has been successfully implemented, there remains exciting future work to further refine and expand its capabilities.  
+I look forward to continuing my contributions to **xeus-cpp**, **CppInterOp**, and **clang-repl**, and to further advancing open-source compiler and debugging infrastructure.  
+