Check compiler versions at Python setup time

1 files changed, 31 insertions, 0 deletions

diff --git a/src/python/grpcio/commands.py b/src/python/grpcio/commands.py
index 6a7df8e1c1..e1a3f4bed3 100644
--- a/src/python/grpcio/commands.py
+++ b/src/python/grpcio/commands.py
@@ -40,6 +40,17 @@ import setuptools
 from setuptools.command import build_py
 from setuptools.command import test
 
+# Because we need to support building without Cython but simultaneously need to
+# subclass its command class when we need to and because distutils requires a
+# special hook to acquire a command class, we attempt to import Cython's
+# build_ext, and if that fails we import setuptools'.
+try:
+  # Due to the strange way Cython's Distutils module re-imports build_ext, we
+  # import the build_ext class directly.
+  from Cython.Distutils.build_ext import build_ext
+except ImportError:
+  from setuptools.command.build_ext import build_ext
+
 PYTHON_STEM = os.path.dirname(os.path.abspath(__file__))
 
 CONF_PY_ADDENDUM = """
@@ -168,6 +179,26 @@ class BuildPy(build_py.build_py):
     build_py.build_py.run(self)
 
 
+class BuildExt(build_ext):
+  """Custom build_ext command to enable compiler-specific flags."""
+
+  C_OPTIONS = {
+      'unix': ('-pthread', '-std=gnu99'),
+      'msvc': (),
+  }
+  LINK_OPTIONS = {}
+
+  def build_extensions(self):
+    compiler = self.compiler.compiler_type
+    if compiler in BuildExt.C_OPTIONS:
+      for extension in self.extensions:
+        extension.extra_compile_args += list(BuildExt.C_OPTIONS[compiler])
+    if compiler in BuildExt.LINK_OPTIONS:
+      for extension in self.extensions:
+        extension.extra_link_args += list(BuildExt.LINK_OPTIONS[compiler])
+    build_ext.build_extensions(self)
+
+
 class Gather(setuptools.Command):
   """Command to gather project dependencies."""