Extern-C-Prototype-Check.yml

name: CI extern "C" prototype parity

on:
  push:
    branches:
      - master
  pull_request:
    branches:
      - master
  workflow_dispatch:

permissions:
  contents: read

concurrency:
  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
  cancel-in-progress: ${{ github.ref != 'refs/heads/master' }}

jobs:
  extern-c-prototype-check:
    name: extern "C" definitions match their C prototypes
    runs-on: ubuntu-latest
    timeout-minutes: 10

    steps:
      - name: Checkout
        uses: actions/checkout@v5

      - name: Checker self-test
        shell: bash
        run: |
          set -eu
          # Fixture pass: a matching definition is clean, a definition
          # with a parameter more than its prototype (the shape of the
          # 0b2613d Xbox boot crash) is flagged, and a parameter of
          # another type is flagged.
          python3 tools/extern_c_prototype_check.py --selftest

      - name: Tree check
        shell: bash
        run: |
          set -eu
          # A .cpp file that defines a win32_common.h function under
          # extern "C" without including the header (uwp_main.cpp) is
          # never checked against the prototype by any compiler: the
          # linker matches on the name alone. This is the check that
          # compares the two, for every such definition in the tree.
          python3 tools/extern_c_prototype_check.py