build: consolidate toolchain helpers

.github/workflows/ci.yml

@@ -633,6 +633,9 @@ jobs:
     permissions:
       contents: read
     steps:
+      - name: Enable Git symlinks (Windows, must precede checkout)
+        run: git config --global core.symlinks true
+
       - name: Checkout repository
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1  # v7.0.1
         with:

.github/workflows/coverage.yml

@@ -232,6 +232,9 @@ jobs:
       CUDA_PYTHON_COVERAGE: "1"
       CUDA_VER: ${{ needs.coverage-vars.outputs.CUDA_VER }}
     steps:
+      - name: Enable Git symlinks (Windows, must precede checkout)
+        run: git config --global core.symlinks true
+
       - name: Checkout ${{ github.event.repository.name }}
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1  # v7.0.1
         with:
@@ -348,6 +351,9 @@ jobs:
       run:
         shell: bash --noprofile --norc -xeuo pipefail {0}
     steps:
+      - name: Enable Git symlinks (Windows, must precede checkout)
+        run: git config --global core.symlinks true
+
       - name: Checkout ${{ github.event.repository.name }}
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1  # v7.0.1
         with:

.pre-commit-config.yaml

@@ -81,13 +81,6 @@ repos:
         language: python
         files: '^cuda_core/tests/.*\.py$'
 
-      - id: check-build-hooks-sync
-        name: Check shared build_hooks.py blocks are in sync
-        entry: python ./toolshed/check_build_hooks_sync.py
-        language: python
-        files: '^(cuda_bindings|cuda_core)/build_hooks\.py$'
-        pass_filenames: false
-
       - id: no-markdown-in-docs-source
         name: Prevent markdown files in docs/source directories
         entry: bash -c

cuda_bindings/AGENTS.md

@@ -19,7 +19,10 @@ subpackage in the `cuda-python` monorepo.
 - **Platform internals**: `cuda/bindings/_internal/` contains
   platform-specific implementation files and support code.
 - **Build backend**: `build_hooks.py` drives extension configuration and
-  Cythonization.
+  Cythonization. Logic shared with `cuda_core` (toolchain selection, the
+  compiler flag set, the Cython cache helpers and the rebuild stamps) lives
+  in `_build_shared.py`; `cuda_core/_build_shared.py` is a symlink to this
+  file, so an edit here changes both packages.
 
 ## Generated-source workflow
 

cuda_bindings/MANIFEST.in

@@ -6,3 +6,5 @@ recursive-include cuda/ *.pyx *.pxd *.pxi *.pyx.in *.pxd.in *.pxi.in *.h
 # to the payload, causing file copying to the build environment failed
 exclude cuda/bindings cuda?bindings
 exclude cuda/bindings/_bindings cuda?bindings?_bindings
+# canonical shared PEP 517 helper (cuda_core/_build_shared.py symlinks to the cuda_bindings copy)
+include _build_shared.py