GCC 10 build failures at BIRD 2.0.7

[Toke Høiland-Jørgensen]

Robert Scheck <bird at robert-scheck.de> writes:

> Hello folks,
>
> trying to build BIRD 2.0.7 using GCC 10 (which landed in Fedora these days)
> leads to a build failure like this:
>
> /usr/bin/ld: obj/conf/cf-lex.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/conf/conf.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/filter/filter.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/filter/data.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/filter/f-util.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/filter/tree.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/filter/trie.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/filter/inst-gen.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/nest/a-path.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/nest/a-set.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/nest/cmds.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/nest/iface.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/nest/neighbor.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/nest/proto.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/nest/rt-attr.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/nest/rt-dev.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/nest/rt-fib.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/nest/rt-show.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/nest/rt-table.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/bfd/bfd.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/bfd/packets.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/babel/babel.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/babel/packets.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/bgp/attrs.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/bgp/bgp.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/bgp/packets.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/mrt/mrt.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/ospf/dbdes.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/ospf/hello.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/ospf/iface.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/ospf/lsack.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/ospf/lsalib.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/ospf/lsreq.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/ospf/lsupd.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/ospf/neighbor.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/ospf/ospf.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/ospf/packet.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/ospf/rt.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/ospf/topology.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/perf/perf.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/pipe/pipe.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/radv/packets.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/radv/radv.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/rip/packets.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/rip/rip.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/rpki/rpki.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/rpki/packets.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/rpki/tcp_transport.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/rpki/ssh_transport.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/rpki/transport.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/proto/static/static.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/sysdep/linux/netlink.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/sysdep/unix/krt.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> /usr/bin/ld: obj/sysdep/unix/main.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: multiple definition of `rta_dest_names'; obj/conf/cf-parse.tab.o:/builddir/build/BUILD/bird-2.0.7/./nest/route.h:461: first defined here
> collect2: error: ld returned 1 exit status
>
> https://gcc.gnu.org/gcc-10/porting_to.html gives a pointer that this is
> related to a common mistake in C related to missing "extern" to global
> variables in a header file.
>
> Any chance for a patch (rather to suggest -fno-common)? Thank you.

I think the below patch (against master) ought to fix it? Don't have a
GCC v10 handy to test with, but at least it doesn't seem to break
anything on GCC v9 :)

I think the same patch ought to apply against Bird 2.0.7 as well...

-Toke



diff --git a/nest/route.h b/nest/route.h
index d2a07f09..b927db5f 100644
--- a/nest/route.h
+++ b/nest/route.h
@@ -458,7 +458,7 @@ typedef struct rta {
                                           protocol-specific metric is availabe */
 
 
-const char * rta_dest_names[RTD_MAX];
+extern const char * rta_dest_names[RTD_MAX];
 
 static inline const char *rta_dest_name(uint n)
 { return (n < RTD_MAX) ? rta_dest_names[n] : "???"; }