Merge branch 'main' into fea-global-setup

.clangd

@@ -0,0 +1,62 @@
+# https://clangd.llvm.org/config
+
+# Apply a config conditionally to all C files
+If:
+  PathMatch: .*\.(c|h)$
+
+---
+
+# Apply a config conditionally to all C++ files
+If:
+  PathMatch: .*\.(c|h)pp
+
+---
+
+# Apply a config conditionally to all CUDA files
+If:
+  PathMatch: .*\.cuh?
+CompileFlags:
+  Add:
+    # Allow variadic CUDA functions
+    - "-Xclang=-fcuda-allow-variadic-functions"
+
+---
+
+# Tweak the clangd parse settings for all files
+CompileFlags:
+  Compiler: clang++
+  CompilationDatabase: .
+  Add:
+    - -x
+    - cuda
+    # report all errors
+    - "-ferror-limit=0"
+    - "-ftemplate-backtrace-limit=0"
+    - "-std=c++17"
+  Remove:
+    # strip CUDA fatbin args
+    - "-Xfatbin*"
+    - "-Xcompiler*"
+    - "-Xcudafe*"
+    - "-rdc=*"
+    - "-gpu=*"
+    - "--diag_suppress*"
+    # strip CUDA arch flags
+    - "-gencode*"
+    - "--generate-code*"
+    # strip gcc's -fcoroutines
+    - -fcoroutines
+    # strip CUDA flags unknown to clang
+    - "-ccbin*"
+    - "--compiler-options*"
+    - "--expt-extended-lambda"
+    - "--expt-relaxed-constexpr"
+    - "-forward-unknown-to-host-compiler"
+    - "-Werror=cross-execution-space-call"
+Diagnostics:
+  Suppress:
+    - "variadic_device_fn"
+    - "attributes_not_allowed"
+    # The NVHPC version of _NVCXX_EXPAND_PACK macro triggers this clang error.
+    # Temporarily suppressing it, but should probably fix
+    - "template_param_shadow"

.devcontainer/README.md

@@ -0,0 +1,198 @@
+> **Note**
+> The instructions in this README are specific to Linux development environments. Instructions for Windows are coming soon!
+
+[![Open in GitHub Codespaces](https://github.com/codespaces/badge.svg)](https://codespaces.new/NVIDIA/cccl?quickstart=1&devcontainer_path=.devcontainer%2Fdevcontainer.json)
+
+# CCCL Dev Containers
+
+CCCL uses [Development Containers](https://containers.dev/) to provide consistent and convenient development environments for both local development and for CI. This guide covers setup in [Visual Studio Code](#quickstart-vscode-recommended) and [Docker](#quickstart-docker-manual-approach). The guide also provides additional instructions in case you want use WSL.
+
+## Table of Contents
+1. [Quickstart: VSCode (Recommended)](#vscode)
+2. [Quickstart: Docker (Manual Approach)](#docker)
+3. [Quickstart: Using WSL](#wsl)
+
+## Quickstart: VSCode (Recommended) <a name="vscode"></a>
+
+### Prerequisites
+- [Visual Studio Code](https://code.visualstudio.com/)
+- [Remote - Containers extension](https://marketplace.visualstudio.com/items?itemName=ms-vscode-remote.remote-containers)
+- [NVIDIA Container Toolkit](https://docs.nvidia.com/datacenter/cloud-native/container-toolkit/latest/install-guide.html)
+- [Docker](https://docs.docker.com/engine/install/) - This is only for completeness because it should already be implicitly installed by the Dev Containers extension
+
+### Steps
+
+1. Clone the Repository
+    ```bash
+    git clone https://github.com/nvidia/cccl.git
+    ```
+2. Open the cloned directory in VSCode
+
+3. Launch a Dev Container by clicking the prompt suggesting to "Reopen in Container"
+
+   ![Shows "Reopen in Container" prompt when opening the cccl directory in VScode.](./img/reopen_in_container.png)
+
+   - Alternatively, use the Command Palette to start a Dev Container. Press `Ctrl+Shift+P` to open the Command Palette. Type "Remote-Containers: Reopen in Container" and select it.
+
+     ![Shows "Reopen in Container" in command pallete.](./img/open_in_container_manual.png)
+
+4. Select an environment with the desired CTK and host compiler from the list:
+
+   ![Shows list of available container environments.](./img/container_list.png)
+
+5. VSCode will initialize the selected Dev Container. This can take a few minutes the first time.
+
+6. Once initialized, the local `cccl/` directory is mirrored into the container to ensure any changes are persistent.
+
+7. Done! See the [contributing guide](../CONTRIBUTING.md#building-and-testing) for instructions on how to build and run tests.
+
+### (Optional) Authenticate with GitHub for `sccache`
+
+After starting the container, there will be a prompt to authenticate with GitHub. This grants access to a [`sccache`](https://github.com/mozilla/sccache) server shared with CI and greatly accelerates local build times. This is currently limited to NVIDIA employees belonging to the `NVIDIA` or `rapidsai` GitHub organizations.
+
+Without authentication to the remote server, `sccache` will still accelerate local builds by using a filesystem cache.
+
+Follow the instructions in the prompt as below and enter the one-time code at https://github.com/login/device
+
+  ![Shows authentication with GitHub to access sccache bucket.](./img/github_auth.png)
+
+To manually trigger this authentication, execute the `devcontainer-utils-vault-s3-init` script within the container.
+
+For more information about the sccache configuration and authentication, see the documentation at [`rapidsai/devcontainers`](https://github.com/rapidsai/devcontainers/blob/branch-23.10/USAGE.md#build-caching-with-sccache).
+
+## Quickstart: Docker (Manual Approach) <a name="docker"></a>
+
+### Prerequisites
+- [Docker](https://docs.docker.com/desktop/install/linux-install/)
+
+### Steps
+1. Clone the repository and use the [`launch.sh`](./launch.sh) script to launch the default container environment
+    ```bash
+    git clone https://github.com/nvidia/cccl.git
+    cd cccl
+    ./.devcontainer/launch.sh --docker
+    ```
+    This script starts an interactive shell as the `coder` user inside the container with the local `cccl/` directory mirrored into `/home/coder/cccl`.
+
+    For specific environments, use the `--cuda` and `--host` options:
+    ```bassh
+    ./.devcontainer/launch.sh --docker --cuda 12.2 --host gcc10
+    ```
+    See `./.devcontainer/launch.sh --help` for more information.
+
+2. Done. See the [contributing guide](../CONTRIBUTING.md#building-and-testing) for instructions on how to build and run tests.
+
+## Available Environments
+
+CCCL provides environments for both the oldest and newest supported CUDA versions with all compatible host compilers.
+
+Look in the [`.devcontainer/`](.) directory to see the available configurations. The top-level [`devcontainer.json`](./devcontainer.json) serves as the default environment. All `devcontainer.json` files in the `cuda<CTK_VERSION>-<HOST-COMPILER>` sub-directories are variations on this top-level file, with different base images for the different CUDA and host compiler versions.
+
+## VSCode Customization
+
+By default, CCCL's Dev Containers come with certain VSCode settings and extensions configured by default, as can be seen in the [`devcontainer.json`](./devcontainer.json) file. This can be further customized by users without needing to modify the `devcontainer.json` file directly.
+
+For extensions, the [`dev.containers.defaultExtensions` setting](https://code.visualstudio.com/docs/devcontainers/containers#_always-installed-extensions) allows listing extensions that will always be installed.
+
+For more general customizations, VSCode allows using a dotfile repository. See the [VSCode documentation](https://code.visualstudio.com/docs/devcontainers/containers#_personalizing-with-dotfile-repositories) for more information.
+
+## GitHub Codespaces
+
+[![Open in GitHub Codespaces](https://github.com/codespaces/badge.svg)](https://codespaces.new/NVIDIA/cccl?quickstart=1&devcontainer_path=.devcontainer%2Fdevcontainer.json)
+
+One of the benefits of Dev Containers is that they integrate natively with [GitHub Codespaces](https://github.com/features/codespaces). Codespaces provide a VSCode development environment right in your browser running on a machine in the cloud. This provides a truly one-click, turnkey development environment where you can develop, build, and test with no other setup required.
+
+Click the badge above or [click here](https://codespaces.new/NVIDIA/cccl?quickstart=1&devcontainer_path=.devcontainer%2Fdevcontainer.json) to get started with CCCL's Dev Containers on Codespaces. This will start the default Dev Container environment. [Click here](https://github.com/codespaces/new?hide_repo_select=true&ref=main&repo=296416761&skip_quickstart=true) to start a Codespace with a particular environment and hardware configuration as shown:
+
+   ![Shows configuring a Codespace with a custom environment](../docs/images/codespaces.png)
+
+## For Maintainers: The `make_devcontainers.sh` Script
+
+### Overview
+
+[`make_devcontainers.sh`](./make_devcontainers.sh) generates devcontainer configurations for the unique combinations of CUDA Toolkit (CTK) versions and host compilers in [`ci/matrix.yaml`](../ci/matrix.yaml).
+
+### How It Works:
+
+1. Parses the matrix from `ci/matrix.yaml`.
+2. Use the top-level [`.devcontainer/devcontainer.json`](./devcontainer.json) as a template. For each unique combination of CTK version and host compiler, generate a corresponding `devcontainer.json` configuration, adjusting only the base Docker image to match the desired environment.
+3. Place the generated configurations in the `.devcontainer` directory, organizing them into subdirectories following the naming convention `cuda<CTK_VERSION>-<COMPILER_VERSION>`.
+
+For more information, see the `.devcontainer/make_devcontainers.sh --help` message.
+
+**Note**: When adding or updating supported environments, modify `matrix.yaml` and then rerun this script to synchronize the `devcontainer` configurations.
+
+## Quickstart: Using WSL <a name="wsl"></a>
+
+> [!NOTE]
+> _Make sure you have the Nvidia driver installed on your Windows host before moving further_. Type in `nvidia-smi` for verification.
+
+### Install WSL on your Windows host
+
+> [!WARNING]
+> Disclaimer: This guide was developed for WSL 2 on Windows 11.
+
+1. Launch a Windows terminal (_e.g. Powershell_) as an administrator.
+
+2. Install WSL 2 by running:
+```bash
+wsl --install 
+```
+This should probably install Ubuntu distro as a default.
+
+3. Restart your computer and run `wsl -l -v` on a Windows terminal to verify installation.
+
+<h3 id="prereqs"> Install prerequisites and VS Code extensions</h3>
+
+4. Launch your WSL/Ubuntu terminal by running `wsl` in Powershell.
+
+5. Install the [WSL extension](ms-vscode-remote.remote-wsl) on VS Code.
+
+    - `Ctrl + Shift + P` and select `WSL: Connect to WSL` (it will prompt you to install the WSL extension).
+
+    - Make sure you are connected to WSL with VS Code by checking the bottom left corner of the VS Code window (should indicate "WSL: Ubuntu" in our case).
+
+6. Install the [Dev Containers extension](ms-vscode-remote.remote-containers) on VS Code.
+
+    - In a vanilla system you should be prompted to install `Docker` at this point, accept it. If it hangs you might have to restart VS Code after that.
+
+7. Install the [NVIDIA Container Toolkit](https://docs.nvidia.com/datacenter/cloud-native/container-toolkit/latest/install-guide.html). **Make sure you install the WSL 2 version and not the native Linux one**. This builds on top of Docker so make sure you have Docker properly installed (run `docker --version`).
+
+8. Open `/etc/docker/daemon.json` from within your WSL system (if the file does not exist, create it) and add the following:
+
+```json
+{
+    "runtimes": {
+        "nvidia": {
+            "path": "nvidia-container-runtime",
+            "runtimeArgs": []
+        }
+    }
+}
+```
+
+then run `sudo systemctl restart docker.service`.
+
+---
+### Build CCCL in WSL using Dev Containers
+
+9. Still on your WSL terminal run `git clone https://github.com/NVIDIA/cccl.git`
+
+
+10. Open the CCCL cloned repo in VS Code ( `Ctrl + Shift + P `, select `File: Open Folder...` and select the path where your CCCL clone is located).
+
+11. If prompted, choose `Reopen in Container`.
+    
+    - If you are not prompted just type `Ctrl + Shift + P` and `Dev Containers: Open Folder in Container ...`.
+
+12. Verify that Dev Container was configured properly by running `nvidia-smi` in your Dev Container terminal. For a proper configuration it is important for the steps in [Install prerequisites and VS Code extensions](#prereqs) to be followed in a precise order.
+
+From that point on, the guide aligns with our [existing Dev Containers native Linux guide](https://github.com/NVIDIA/cccl/blob/main/.devcontainer/README.md) with just one minor potential alteration:
+
+13. If WSL was launched without the X-server enabled, when asked to "authenticate Git with your Github credentials", if you answer **Yes**, the browser might not open automatically, with the following error message. 
+
+> Failed opening a web browser at https://github.com/login/device
+  exec: "xdg-open,x-www-browser,www-browser,wslview": executable file not found in $PATH
+  Please try entering the URL in your browser manually
+
+In that case type in the address manually in your web browser https://github.com/login/device and fill in the one-time code.

.devcontainer/cuda11.1-gcc7/devcontainer.json

@@ -0,0 +1,46 @@
+{
+  "shutdownAction": "stopContainer",
+  "image": "rapidsai/devcontainers:24.06-cpp-gcc7-cuda11.1-ubuntu18.04",
+  "hostRequirements": {
+    "gpu": "optional"
+  },
+  "initializeCommand": [
+    "/bin/bash",
+    "-c",
+    "mkdir -m 0755 -p ${localWorkspaceFolder}/.{aws,cache,config}"
+  ],
+  "containerEnv": {
+    "SCCACHE_REGION": "us-east-2",
+    "SCCACHE_BUCKET": "rapids-sccache-devs",
+    "VAULT_HOST": "https://vault.ops.k8s.rapids.ai",
+    "HISTFILE": "${containerWorkspaceFolder}/.cache/._bash_history",
+    "DEVCONTAINER_NAME": "cuda11.1-gcc7",
+    "CCCL_CUDA_VERSION": "11.1",
+    "CCCL_HOST_COMPILER": "gcc",
+    "CCCL_HOST_COMPILER_VERSION": "7",
+    "CCCL_BUILD_INFIX": "cuda11.1-gcc7"
+  },
+  "workspaceFolder": "/home/coder/${localWorkspaceFolderBasename}",
+  "workspaceMount": "source=${localWorkspaceFolder},target=/home/coder/${localWorkspaceFolderBasename},type=bind,consistency=consistent",
+  "mounts": [
+    "source=${localWorkspaceFolder}/.aws,target=/home/coder/.aws,type=bind,consistency=consistent",
+    "source=${localWorkspaceFolder}/.cache,target=/home/coder/.cache,type=bind,consistency=consistent",
+    "source=${localWorkspaceFolder}/.config,target=/home/coder/.config,type=bind,consistency=consistent"
+  ],
+  "customizations": {
+    "vscode": {
+      "extensions": [
+        "llvm-vs-code-extensions.vscode-clangd",
+        "xaver.clang-format"
+      ],
+      "settings": {
+        "editor.defaultFormatter": "xaver.clang-format",
+        "clang-format.executable": "/usr/local/bin/clang-format",
+        "clangd.arguments": [
+          "--compile-commands-dir=${workspaceFolder}"
+        ]
+      }
+    }
+  },
+  "name": "cuda11.1-gcc7"
+}

.devcontainer/cuda11.1-gcc8/devcontainer.json

@@ -0,0 +1,46 @@
+{
+  "shutdownAction": "stopContainer",
+  "image": "rapidsai/devcontainers:24.06-cpp-gcc8-cuda11.1-ubuntu18.04",
+  "hostRequirements": {
+    "gpu": "optional"
+  },
+  "initializeCommand": [
+    "/bin/bash",
+    "-c",
+    "mkdir -m 0755 -p ${localWorkspaceFolder}/.{aws,cache,config}"
+  ],
+  "containerEnv": {
+    "SCCACHE_REGION": "us-east-2",
+    "SCCACHE_BUCKET": "rapids-sccache-devs",
+    "VAULT_HOST": "https://vault.ops.k8s.rapids.ai",
+    "HISTFILE": "${containerWorkspaceFolder}/.cache/._bash_history",
+    "DEVCONTAINER_NAME": "cuda11.1-gcc8",
+    "CCCL_CUDA_VERSION": "11.1",
+    "CCCL_HOST_COMPILER": "gcc",
+    "CCCL_HOST_COMPILER_VERSION": "8",
+    "CCCL_BUILD_INFIX": "cuda11.1-gcc8"
+  },
+  "workspaceFolder": "/home/coder/${localWorkspaceFolderBasename}",
+  "workspaceMount": "source=${localWorkspaceFolder},target=/home/coder/${localWorkspaceFolderBasename},type=bind,consistency=consistent",
+  "mounts": [
+    "source=${localWorkspaceFolder}/.aws,target=/home/coder/.aws,type=bind,consistency=consistent",
+    "source=${localWorkspaceFolder}/.cache,target=/home/coder/.cache,type=bind,consistency=consistent",
+    "source=${localWorkspaceFolder}/.config,target=/home/coder/.config,type=bind,consistency=consistent"
+  ],
+  "customizations": {
+    "vscode": {
+      "extensions": [
+        "llvm-vs-code-extensions.vscode-clangd",
+        "xaver.clang-format"
+      ],
+      "settings": {
+        "editor.defaultFormatter": "xaver.clang-format",
+        "clang-format.executable": "/usr/local/bin/clang-format",
+        "clangd.arguments": [
+          "--compile-commands-dir=${workspaceFolder}"
+        ]
+      }
+    }
+  },
+  "name": "cuda11.1-gcc8"
+}