Install a dummy <rpc/netdb.h> when not building sunrpc/.

ChangeLog

@@ -1,3 +1,8 @@
+2015-07-08  Roland McGrath  <roland@hack.frob.com>
+
+	* resolv/rpc/netdb.h: New file.
+	* resolv/Makefile [sunrpc not in $(subdirs)] (headers): Add it.
+
 2015-07-08  Adhemerval Zanella  <adhemerval.zanella@linaro.org>
 
 	* stdio-common/tst-fmemopen2.c (do_test): Add test for NULL and zero

resolv/Makefile

@@ -72,6 +72,13 @@ xtests-special += $(objpfx)mtrace-tst-leaks2.out
 endif
 endif
 
+ifeq (,$(filter sunrpc,$(subdirs)))
+# The netdb.h we install does '#include <rpc/netdb.h>', so one must exist.
+# If sunrpc/ is built in this configuration, it installs a real <rpc/netdb.h>.
+# If that's not going to happen, install our dummy file.
+headers += rpc/netdb.h
+endif
+
 generated += mtrace-tst-leaks.out tst-leaks.mtrace \
 	     mtrace-tst-leaks2.out tst-leaks2.mtrace
 

resolv/rpc/netdb.h

@@ -0,0 +1,3 @@
+/* This is a dummy file for <rpc/netdb.h>, which is included by <netdb.h>.
+   This file is installed when the C library does not support the SunRPC
+   interfaces (including 'struct rpcent' et al) at all.  */