--- ./rpcsvc/Makefile.in.ORIGIN	2018-05-28 02:27:44.000000000 -0500
+++ ./rpcsvc/Makefile.in	2019-06-20 16:46:14.000000000 -0500
@@ -531,7 +531,11 @@
 
 
 %.h: %.x
-	$(top_builddir)/rpcgen/rpcgen -h -o $@ $<
+	if test -e $(CPP); then \
+	  $(top_builddir)/rpcgen/rpcgen -Y `dirname $(CPP)` -h -o $@ $< ; \
+	else \
+	  $(top_builddir)/rpcgen/rpcgen -h -o $@ $< ; \
+	fi
 
 # Tell versions [3.59,3.63) of GNU make to not export all variables.
 # Otherwise a system limit (for SysV at least) may be exceeded.
--- ./rpcgen/rpc_main.c.ORIGIN	2018-05-28 09:26:50 +0200
+++ ./rpcgen/rpc_main.c	2019-06-25 11:31:34 +0200
@@ -83,7 +83,13 @@
 
 static const char *svcclosetime = "120";
 static int cppDefined;	/* explicit path for C preprocessor */
+#ifdef _AIX
+/* On AIX /lib/cpp and /usr/lib/cpp are symlinks to XL C /usr/ccs/lib/cpp */
+/* and the AIX version of cpp is not at the same feature level as GCC     */
+static const char *CPP = "/opt/freeware/bin/cpp";
+#else
 static const char *CPP = "/lib/cpp";
+#endif
 static const char CPPFLAGS[] = "-C";
 static char *pathbuf;
 static int cpp_pid;