diff --git a/src/backend/replication/Makefile b/src/backend/replication/Makefile
index 6f17b08a6a..b73370eaa9 100644
--- a/src/backend/replication/Makefile
+++ b/src/backend/replication/Makefile
@@ -12,7 +12,7 @@ subdir = src/backend/replication
 top_builddir = ../../..
 include $(top_builddir)/src/Makefile.global
 
-override CPPFLAGS := -I$(srcdir) $(CPPFLAGS)
+override CPPFLAGS := -I. -I$(srcdir) $(CPPFLAGS)
 
 OBJS = walsender.o walreceiverfuncs.o walreceiver.o basebackup.o \
 	repl_gram.o slot.o slotfuncs.o syncrep.o