sunrpc: Remove hidden aliases for global data symbols (bug 26210)

It is generally not possible to add hidden aliases for global data
symbols: If the main executable contains a copy relocation against
the symbol, the hidden aliases keep pointing to the glibc-internal
copy of the symbol, instead of the symbol actually used by the
application.

Fixes commit 89aacb513e ("sunrpc:
Remove stray exports without --enable-obsolete-rpc [BZ #23166]").

Reviewed-by: Carlos O'Donell <carlos@redhat.com>

include/rpc/clnt.h

@@ -28,7 +28,6 @@ libc_hidden_proto (clntudp_create)
 libc_hidden_proto (get_myaddress)
 libc_hidden_proto (clntunix_create)
 libc_hidden_proto (__libc_clntudp_bufcreate)
-libc_hidden_proto (rpc_createerr)
 
 # endif /* !_ISOMAC */
 #endif

include/rpc/svc.h

@@ -3,10 +3,6 @@
 
 # ifndef _ISOMAC
 
-libc_hidden_proto (svc_pollfd)
-libc_hidden_proto (svc_max_pollfd)
-libc_hidden_proto (svc_fdset)
-
 libc_hidden_proto (xprt_register)
 libc_hidden_proto (xprt_unregister)
 libc_hidden_proto (svc_register)

sunrpc/rpc_common.c

@@ -48,10 +48,14 @@ libc_hidden_nolink_sunrpc (_null_auth, GLIBC_2_0)
 /* The variables need the nocommon attribute, so that it is possible
    to create aliases and specify symbol versions.  */
 fd_set svc_fdset  __attribute__ ((nocommon));
-libc_hidden_nolink_sunrpc (svc_fdset, GLIBC_2_0)
 struct rpc_createerr rpc_createerr  __attribute__ ((nocommon));
-libc_hidden_nolink_sunrpc (rpc_createerr, GLIBC_2_0)
 struct pollfd *svc_pollfd  __attribute__ ((nocommon));
-libc_hidden_nolink_sunrpc (svc_pollfd, GLIBC_2_2)
 int svc_max_pollfd  __attribute__ ((nocommon));
-libc_hidden_nolink_sunrpc (svc_max_pollfd, GLIBC_2_2)
+#ifdef SHARED
+# ifndef EXPORT_RPC_SYMBOLS
+compat_symbol (libc, svc_fdset, svc_fdset, GLIBC_2_0);
+compat_symbol (libc, rpc_createerr, rpc_createerr, GLIBC_2_0);
+compat_symbol (libc, svc_pollfd, svc_pollfd, GLIBC_2_2);
+compat_symbol (libc, svc_max_pollfd, svc_max_pollfd, GLIBC_2_2);
+# endif
+#endif