libmemcached is a c++ library.  To link statically we need to use cxx rather
than cc to ensure libc++ is linked in.

--- Makefile.in.orig	2017-03-09 13:00:34.016595000 -0800
+++ Makefile.in	2017-03-09 13:00:39.656086000 -0800
@@ -74,7 +74,7 @@ files_to_distclean = Makefile config.h c
 all: ccache$(EXEEXT)
 
 ccache$(EXEEXT): $(ccache_objs) $(extra_libs)
-	$(CC) $(all_cflags) -o $@ $(ccache_objs) $(LDFLAGS) $(extra_libs) $(LIBS)
+	$(CXX) $(all_cflags) -o $@ $(ccache_objs) $(LDFLAGS) $(extra_libs) $(LIBS)
 
 .PHONY: install
 install: all $(srcdir)/ccache.1