Apply pyodide emscripten patches

Author: oscarbenjamin

.github/workflows/buildwheel.yml

@@ -2,6 +2,9 @@ name: Build
 
 on: [push, pull_request]
 
+env:
+  PYODIDE_VERSION: 0.28.2
+
 jobs:
   build_wheels:
     name: ${{ matrix.name }}
@@ -99,13 +102,25 @@ jobs:
           version: ${{ matrix.emscripten_version }}
           actions-cache-folder: emsdk-cache
 
+      - if: ${{ matrix.kind == 'pyodide' }}
+        name: Check out Emscripten patches for Pyodide
+        uses: actions/checkout@v6.0.2
+        with:
+          repository: pyodide/pyodide
+          ref: ${{ env.PYODIDE_VERSION }}
+          path: pyodide-patches
+          sparse-checkout: |
+            emsdk/patches/
+
         # ------------- actual build ------------- #
 
       - name: Build wheels
         uses: pypa/cibuildwheel@298ed2fb2c105540f5ed055e8a6ad78d82dd3a7e # v3.3.1
         env:
           CIBW_PLATFORM: ${{ matrix.cibw_platform }}
           CIBW_BUILD: ${{ matrix.cibw_build }}
+          CIBW_PYODIDE_VERSION: ${{ env.PYODIDE_VERSION }}
+          PYODIDE_EMSCRIPTEN_VERSION: ${{ matrix.kind == 'pyodide' && matrix.emscripten_version || '' }}
           # override setting in pyproject.toml to use msys2 instead of msys64 bash
           CIBW_BEFORE_ALL_WINDOWS: ${{ matrix.os == 'windows-11-arm' && 'msys2 -c bin/cibw_before_all_windows_arm64.sh' || 'msys2 -c bin/cibw_before_all_windows_amd64.sh' }}
 
@@ -183,8 +198,6 @@ jobs:
     needs: build_wheels
     name: Test Pyodide wheel
     runs-on: ubuntu-22.04
-    env:
-      PYODIDE_VERSION: 0.28.2
 
     steps:
       - uses: actions/setup-python@v6

bin/cibw_before_build_pyodide.sh

@@ -0,0 +1,12 @@
+#!/bin/bash
+
+set -euo pipefail
+
+python -m pip install wheel auditwheel_emscripten
+
+EMSCRIPTEN_DIR="$HOME/.cache/cibuildwheel/emsdk-$PYODIDE_EMSCRIPTEN_VERSION/emsdk-$PYODIDE_EMSCRIPTEN_VERSION/upstream/emscripten"
+
+for patch_file in pyodide-patches/emsdk/patches/*.patch; do
+  echo "Applying Pyodide Emscripten patch $(basename "$patch_file")"
+  patch -p1 --verbose -d "$EMSCRIPTEN_DIR" < "$patch_file"
+done

pyproject.toml

@@ -179,16 +179,10 @@ repair-wheel-command = [
 
 [tool.cibuildwheel.pyodide]
 before-all = "bin/cibw_before_all_pyodide.sh"
-before-build = "pip install wheel auditwheel_emscripten"
+before-build = "bin/cibw_before_build_pyodide.sh"
+# The pyodide version is set in .github/workflows/buildwheel.yml as
+# CIBW_PYODIDE_VERSION because it is needed also for other things there.
 
-# This needs to be kept in sync with the Pyodide row in
-# .github/workflows/buildwheel.yml. The Pyodide version pins both an
-# Emscripten version and a CPython minor version. The command
-# `pyodide xbuildenv search --all` shows the compatible combinations.
-pyodide-version = "0.28.2"
-
-# GMP, MPFR, and FLINT are built as shared libraries for Pyodide and bundled
-# into the wheel.
 repair-wheel-command = [
 """python bin/cibw_repair_wheel_licenses.py "{wheel}" \
     --license LGPL-3.0-or-later \