diff --git a/src/core/lib/channel/channel_args.c b/src/core/lib/channel/channel_args.c
index 238d176dfae724a968ace9c894d470c9333fc008..247b134938e71ee06e0e57bf61791929b35fc8ba 100644
--- a/src/core/lib/channel/channel_args.c
+++ b/src/core/lib/channel/channel_args.c
@@ -31,6 +31,8 @@
  *
  */
 
+#include <grpc/support/port_platform.h>
+
 #include <limits.h>
 #include <string.h>
 
diff --git a/tools/dockerfile/test/cxx_alpine_x64/Dockerfile b/tools/dockerfile/test/cxx_alpine_x64/Dockerfile
index f9468757da206d4f455d6c1afbb1a55ca90c83aa..b13157f28071d7ab00f799b833eedad4a4e77cad 100644
--- a/tools/dockerfile/test/cxx_alpine_x64/Dockerfile
+++ b/tools/dockerfile/test/cxx_alpine_x64/Dockerfile
@@ -27,7 +27,7 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-FROM alpine:3.3
+FROM alpine:3.5
 
 # Install Git and basic packages.
 RUN apk update && apk add \