Update docs and ci to use emsdk 4.0.9

Author: mcbarton

.github/workflows/deploy-pages.yml

@@ -26,7 +26,7 @@ jobs:
             clang-runtime: '20'
             cling: Off
             micromamba_shell_init: bash
-            emsdk_ver: "3.1.73"
+            emsdk_ver: "4.0.9"
 
     steps:
     - uses: actions/checkout@v5

.github/workflows/emscripten.yml

@@ -27,28 +27,28 @@ jobs:
             cling: Off
             llvm_enable_projects: "clang;lld"
             llvm_targets_to_build: "WebAssembly"
-            emsdk_ver: "3.1.73"
+            emsdk_ver: "4.0.9"
           - name: osx15-arm-clang-repl-20-emscripten
             os: macos-15
             clang-runtime: '20'
             cling: Off
             llvm_enable_projects: "clang;lld"
             llvm_targets_to_build: "WebAssembly"
-            emsdk_ver: "3.1.73"
+            emsdk_ver: "4.0.9"
           - name: ubu24-x86-clang-repl-20-emscripten
             os: ubuntu-24.04
             clang-runtime: '20'
             cling: Off
             llvm_enable_projects: "clang;lld"
             llvm_targets_to_build: "WebAssembly"
-            emsdk_ver: "3.1.73"
+            emsdk_ver: "4.0.9"
           - name: win2025-x86-clang-repl-20-emscripten
             os: windows-2025
             clang-runtime: '20'
             cling: Off
             llvm_enable_projects: "clang;lld"
             llvm_targets_to_build: "WebAssembly"
-            emsdk_ver: "3.1.73"
+            emsdk_ver: "4.0.9"
 
     steps:
     - uses: actions/checkout@v5
@@ -366,25 +366,25 @@ jobs:
             clang-runtime: '20'
             cling: Off
             micromamba_shell_init: bash
-            emsdk_ver: "3.1.73"
+            emsdk_ver: "4.0.9"
           - name: osx15-arm-clang-repl-20-emscripten_wasm
             os: macos-15
             clang-runtime: '20'
             cling: Off
             micromamba_shell_init: bash
-            emsdk_ver: "3.1.73"
+            emsdk_ver: "4.0.9"
           - name: ubu24-arm-clang-repl-20-emscripten_wasm
             os: ubuntu-24.04-arm
             clang-runtime: '20'
             cling: Off
             micromamba_shell_init: bash
-            emsdk_ver: "3.1.73"
+            emsdk_ver: "4.0.9"
           - name: win2025-x86-clang-repl-20-emscripten
             os: windows-2025
             clang-runtime: '20'
             cling: Off
             micromamba_shell_init: powershell
-            emsdk_ver: "3.1.73"
+            emsdk_ver: "4.0.9"
 
     steps:
     - uses: actions/checkout@v5

Emscripten-build-instructions.md

@@ -19,24 +19,24 @@ cd ./CppInterOp-wasm
 ```
 
 To create a wasm build of CppInterOp we make use of the emsdk toolchain. This can be installed by executing (we only currently  
-support version 3.1.73)
+support version 4.0.9)
 ```bash
 git clone https://github.com/emscripten-core/emsdk.git
-./emsdk/emsdk install  3.1.73
+./emsdk/emsdk install  4.0.9
 ```
 
 and to activate the emsdk environment on Linux and osx execute (we are defining SYSROOT_PATH for use later)
 
 ```bash
-./emsdk/emsdk activate 3.1.73
+./emsdk/emsdk activate 4.0.9
 source ./emsdk/emsdk_env.sh
 export SYSROOT_PATH=$PWD/emsdk/upstream/emscripten/cache/sysroot
 ```
 
 and on Windows execute in Powershell
 
 ```powershell
-.\emsdk\emsdk activate 3.1.73
+.\emsdk\emsdk activate 4.0.9
 .\emsdk\emsdk_env.ps1
 $env:PWD_DIR= $PWD.Path
 $env:SYSROOT_PATH="$env:EMSDK/upstream/emscripten/cache/sysroot"

docs/Emscripten-build-instructions.rst

@@ -32,27 +32,27 @@ Now move into this directory using the following command
 
 To create a wasm build of CppInterOp we make use of the emsdk toolchain.
 This can be installed by executing (we only currently support version
-3.1.73)
+4.0.9)
 
 .. code:: bash
 
    git clone https://github.com/emscripten-core/emsdk.git
-   ./emsdk/emsdk install  3.1.73
+   ./emsdk/emsdk install  4.0.9
 
 and to activate the emsdk environment on Linux and osx execute 
 (we are defining SYSROOT_PATH for use later)
 
 .. code:: bash
 
-   ./emsdk/emsdk activate 3.1.73
+   ./emsdk/emsdk activate 4.0.9
    source ./emsdk/emsdk_env.sh
    export SYSROOT_PATH=$PWD/emsdk/upstream/emscripten/cache/sysroot
 
 and on Windows execute in Powershell
 
 .. code:: powershell
 
-   .\emsdk\emsdk activate 3.1.73
+   .\emsdk\emsdk activate 4.0.9
    .\emsdk\emsdk_env.ps1
    $env:PWD_DIR= $PWD.Path
    $env:SYSROOT_PATH="$env:EMSDK/upstream/emscripten/cache/sysroot"
@@ -429,4 +429,4 @@ and on Windows execute
                       --contents xeus-cpp/notebooks/images/marie.png ` 
                       --contents xeus-cpp/notebooks/audio/audio.wav `
                       --XeusAddon.mounts="$env:PREFIX/share/xeus-cpp/tagfiles:/share/xeus-cpp/tagfiles" `
-                      --XeusAddon.mounts="$env:PREFIX/etc/xeus-cpp/tags.d:/etc/xeus-cpp/tags.d"
+                      --XeusAddon.mounts="$env:PREFIX/etc/xeus-cpp/tags.d:/etc/xeus-cpp/tags.d"