Several include files were missing

src/Makefile.am

@@ -23,6 +23,12 @@ libzmq_la_SOURCES = \
     err.hpp \
     fd.hpp \
     fq.hpp \
+    i_encoder.hpp \
+    i_decoder.hpp \
+    i_engine.hpp \
+    i_msg_sink.hpp \
+    i_msg_source.hpp \
+    i_poll_events.hpp \
     io_object.hpp \
     io_thread.hpp \
     ip.hpp \
@@ -134,7 +140,10 @@ libzmq_la_SOURCES = \
     router.cpp \
     dealer.cpp \
     v1_decoder.cpp \
+    v1_decoder.hpp \
     v1_encoder.cpp \
+    v1_encoder.hpp \
+    v1_protocol.hpp \
     xsub.cpp \
     zmq.cpp \
     zmq_utils.cpp