sunrpc: Remove stray exports without --enable-obsolete-rpc [BZ #23166]

This is needed to avoid a warning when linking against libtirpc:

/lib64/libc.so.6: warning: common of `rpc_createerr@@TIRPC_0.3.0' overridden by definition
/usr/lib64/libtirpc.so: warning: defined here

This ld warning is not enabled by default; -Wl,--warn-common enables it.

2018-05-11  Florian Weimer  <fweimer@redhat.com>

	[BZ #23166]
	* include/rpc/clnt.h (rpc_createerr): Declare hidden alias.
	* include/rpc/svc.h (svc_pollfd, svc_max_pollfd, svc_fdset):
	Likewise.
	* sunrpc/rpc_common.c (svc_fdset, rpc_createerr, svc_pollfd)
	(svc_max_pollfd): Add nocommon attribute and hidden alias.  Do not
	export without --enable-obsolete-rpc.
	* sunrpc/svcauth_des.c (svcauthdes_stats): Turn into compatibility
	symbol.  This should not have been exported, ever.

On 05/11/2018 08:57 AM, Florian Weimer wrote:
> This is needed to avoid a warning when linking against libtirpc:
> 
> /lib64/libc.so.6: warning: common of `rpc_createerr@@TIRPC_0.3.0' overridden by definition
> /usr/lib64/libtirpc.so: warning: defined here
> 
> This ld warning is not enabled by default; -Wl,--warn-common enables it.
> 
> 2018-05-11  Florian Weimer  <fweimer@redhat.com>
> 
> 	[BZ #23166]
> 	* include/rpc/clnt.h (rpc_createerr): Declare hidden alias.
> 	* include/rpc/svc.h (svc_pollfd, svc_max_pollfd, svc_fdset):
> 	Likewise.
> 	* sunrpc/rpc_common.c (svc_fdset, rpc_createerr, svc_pollfd)
> 	(svc_max_pollfd): Add nocommon attribute and hidden alias.  Do not
> 	export without --enable-obsolete-rpc.
> 	* sunrpc/svcauth_des.c (svcauthdes_stats): Turn into compatibility
> 	symbol.  This should not have been exported, ever.

LGTM.

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

> diff --git a/include/rpc/clnt.h b/include/rpc/clnt.h
> index a397023a93..80be0a9cec 100644
> --- a/include/rpc/clnt.h
> +++ b/include/rpc/clnt.h
> @@ -28,6 +28,7 @@ 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
> diff --git a/include/rpc/svc.h b/include/rpc/svc.h
> index 465bf4427d..40ba2546a9 100644
> --- a/include/rpc/svc.h
> +++ b/include/rpc/svc.h
> @@ -3,6 +3,10 @@
>  
>  # 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)
> diff --git a/sunrpc/rpc_common.c b/sunrpc/rpc_common.c
> index 710191163c..2d42827a87 100644
> --- a/sunrpc/rpc_common.c
> +++ b/sunrpc/rpc_common.c
> @@ -46,7 +46,14 @@
>     the variable is declared.  So we use the section attribute.  */
>  struct opaque_auth _null_auth __attribute__ ((nocommon));
>  libc_hidden_nolink_sunrpc (_null_auth, GLIBC_2_0)
> -fd_set svc_fdset;
> -struct rpc_createerr rpc_createerr;
> -struct pollfd *svc_pollfd;
> -int svc_max_pollfd;
> +
> +/* 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)
> diff --git a/sunrpc/svcauth_des.c b/sunrpc/svcauth_des.c
> index f99a5a324f..9ce4804239 100644
> --- a/sunrpc/svcauth_des.c
> +++ b/sunrpc/svcauth_des.c
> @@ -87,16 +87,21 @@ static void cache_ref (uint32_t sid); /* note that sid was ref'd */
>  
>  static void invalidate (char *cred); /* invalidate entry in cache */
>  
> -/*
> - * cache statistics
> - */
> +/* Cache statistics.  Accidental historic export without a matching
> +   declaration in any header file.  */
> +#ifndef SHARED
> +static
> +#endif
>  struct
>    {
>      u_long ncachehits;		/* times cache hit, and is not replay */
>      u_long ncachereplays;	/* times cache hit, and is replay */
>      u_long ncachemisses;	/* times cache missed */
>    }
> -svcauthdes_stats;
> +svcauthdes_stats __attribute__ ((nocommon));
> +#ifdef SHARED
> +compat_symbol (libc, svcauthdes_stats, svcauthdes_stats, GLIBC_2_0);
> +#endif
>  
>  /*
>   * Service side authenticator for AUTH_DES
>