c-ares mingw32 support
diff --git a/Rakefile b/Rakefile
index cc02aa1..7f8d3a2 100755
--- a/Rakefile
+++ b/Rakefile
@@ -80,7 +80,7 @@
grpc_config = ENV['GRPC_CONFIG'] || 'opt'
verbose = ENV['V'] || '0'
- env = 'CPPFLAGS="-D_WIN32_WINNT=0x600 -DUNICODE -D_UNICODE -Wno-unused-variable -Wno-unused-result" '
+ env = 'CPPFLAGS="-D_WIN32_WINNT=0x600 -DUNICODE -D_UNICODE -Wno-unused-variable -Wno-unused-result -DCARES_STATICLIB" '
env += 'LDFLAGS=-static '
env += 'SYSTEM=MINGW32 '
env += 'EMBED_ZLIB=true '