Merge pull request cupy#8574 from kmaehashi/fix-setuptools-74

Support building CuPy with setuptools 74

.github/workflows/pretest.yml

@@ -78,7 +78,7 @@ jobs:
 
     - name: Build
       run: |
-        pip install -U pip wheel setuptools==73.0.1
+        pip install -U pip wheel setuptools
         READTHEDOCS=True pip install -v -e .
         ccache --max-size 0.5Gi --cleanup --show-stats
 

install/cupy_builder/_command.py

@@ -143,18 +143,26 @@ def _cythonize(self, nthreads: int) -> None:
             compile_time_env=compile_time_env)
 
     def build_extensions(self) -> None:
+        ctx = cupy_builder.get_context()
         num_jobs = int(os.environ.get('CUPY_NUM_BUILD_JOBS', '4'))
         if num_jobs > 1:
             self.parallel = num_jobs
-            if hasattr(self.compiler, 'initialize'):
-                # Workarounds a bug in setuptools/distutils on Windows by
-                # initializing the compiler before starting a thread.
-                # By default, MSVCCompiler performs initialization in the
-                # first compilation. However, in parallel compilation mode,
-                # the init code runs in each thread and messes up the internal
-                # state as the init code is not locked and is not idempotent.
-                # https://github.com/pypa/setuptools/blob/v60.0.0/setuptools/_distutils/_msvccompiler.py#L322-L327
-                self.compiler.initialize()
+
+        if (sys.platform == 'win32' and
+                hasattr(self.compiler, 'initialize')):  # i.e., MSVCCompiler
+            # Initialize to get path to the host compiler (cl.exe).
+            # This also workarounds a bug in setuptools/distutils on Windows by
+            # initializing the compiler before starting a thread.
+            # By default, MSVCCompiler performs initialization in the
+            # first compilation. However, in parallel compilation mode,
+            # the init code runs in each thread and messes up the internal
+            # state as the init code is not locked and is not idempotent.
+            # https://github.com/pypa/setuptools/blob/v60.0.0/setuptools/_distutils/_msvccompiler.py#L322-L327
+            self.compiler.initialize()
+            if hasattr(self.compiler, 'cc'):
+                cc = self.compiler.cc
+                print(f'Detected host compiler: {cc}')
+                ctx.win32_cl_exe_path = cc
 
         # Compile "*.pyx" files into "*.cpp" files.
         print('Cythonizing...')

install/cupy_builder/_compiler.py

@@ -8,7 +8,6 @@
 from typing import Any, Optional, List
 
 import setuptools
-import setuptools.msvc
 from setuptools import Extension
 
 from cupy_builder._context import Context
@@ -262,8 +261,17 @@ def _find_host_compiler_path(self) -> Optional[str]:
             # The compiler is already on PATH, no extra path needed.
             return None
 
-        vctools: List[str] = setuptools.msvc.EnvironmentInfo(
-            platform.machine()).VCTools
+        if self._context.win32_cl_exe_path is not None:
+            return self._context.win32_cl_exe_path
+
+        if hasattr(setuptools, 'msvc'):  # setuptools<74
+            # TODO(kmaehashi): Remove this code at some point
+            vctools: List[str] = setuptools.msvc.EnvironmentInfo(
+                platform.machine()).VCTools
+        else:
+            print('Warning: cl.exe could not be auto-detected')
+            return None
+
         for path in vctools:
             cl_exe = os.path.join(path, 'cl.exe')
             if os.path.exists(cl_exe):

install/cupy_builder/_context.py

@@ -74,6 +74,9 @@ def __init__(
               f'matching {include_pattern}): {cache_key}')
         self.cupy_cache_key = cache_key
 
+        # Host compiler path for Windows, see `_command.py`.
+        self.win32_cl_exe_path: Optional[str] = None
+
 
 def parse_args(argv: List[str]) -> Tuple[Any, List[str]]:
     parser = argparse.ArgumentParser(add_help=False)