Build grpcio tools on Windows
diff --git a/tools/run_tests/artifact_targets.py b/tools/run_tests/artifact_targets.py
index 72f4f8d..477bd46 100644
--- a/tools/run_tests/artifact_targets.py
+++ b/tools/run_tests/artifact_targets.py
@@ -151,7 +151,8 @@
     elif self.platform == 'windows':
       return create_jobspec(self.name,
                             ['tools\\run_tests\\build_artifact_python.bat',
-                             self.python_version
+                             self.python_version,
+                             '32' if self.arch == 'x86' else '64'
                             ],
                             shell=True)
     else:
diff --git a/tools/run_tests/build_artifact_python.bat b/tools/run_tests/build_artifact_python.bat
index 023d394..636ae0d 100644
--- a/tools/run_tests/build_artifact_python.bat
+++ b/tools/run_tests/build_artifact_python.bat
@@ -52,8 +52,21 @@
 
 python setup.py bdist_wheel
 
+@rem Build gRPC Python tools
+set PATH=C:\msys64\mingw%2\bin;%PATH%
+set CC=C:\msys64\mingw%2\bin\g++.exe
+set CFLAGS=-fno-wrapv
+python tools\distrib\python\make_grpcio_tools.py
+if %2 == 32 (
+  python tools\distrib\python\grpcio_tools\setup.py build_ext -c mingw32
+) else (
+  python tools\distrib\python\grpcio_tools\setup.py build_ext -c mingw32 -DMS_WIN64
+)
+python tools\distrib\python\grpcio_tools\setup.py bdist_wheel
+
 mkdir artifacts
 xcopy /Y /I /S dist\* artifacts\ || goto :error
+xcopy /Y /I /S tools\distrib\python\grpcio_tools\dist\* artifacts\ || goto :error
 
 goto :EOF