Bug#966190: alien-arena: FTBFS with GCC 10: multiple definition of ... due to -fno-common

[Andreas Beckmann]

Source: alien-arena
Version: 7.66+dfsg-5
Severity: serious
Tags: ftbfs sid bullseye
Justification: fails to build from source (but built successfully in the past)
User: debian-gcc at lists.debian.org
Usertags: ftbfs-gcc-10

Hi,

alien-arena started to FTBFS when GCC 10 was made the default compiler:

gcc  -g -O2 -fdebug-prefix-map=/build/alien-arena-7.66+dfsg=. -fstack-protector-strong -Wformat -Werror=format-security -ffast-math -fno-strict-aliasing  -Wl,-z,relro -Wl,-z,now -o alienarena-ded game/alienarena_ded-q_shared.o null/alienarena_ded-cl_null.o qcommon/alienarena_ded-cmd.o qcommon/alienarena_ded-cmodel.o qcommon/alienarena_ded-common.o qcommon/alienarena_ded-crc.o qcommon/alienarena_ded-cvar.o qcommon/alienarena_ded-files.o qcommon/alienarena_ded-htable.o qcommon/alienarena_ded-mdfour.o qcommon/alienarena_ded-net_chan.o qcommon/alienarena_ded-pmove.o server/alienarena_ded-sv_ccmds.o server/alienarena_ded-sv_ents.o server/alienarena_ded-sv_game.o server/alienarena_ded-sv_init.o server/alienarena_ded-sv_main.o server/alienarena_ded-sv_send.o server/alienarena_ded-sv_user.o server/alienarena_ded-sv_world.o unix/alienarena_ded-glob.o unix/alienarena_ded-net_udp.o unix/alienarena_ded-q_shunix.o unix/alienarena_ded-sys_unix.o libgame.a -ljpeg -ldl -lm 
/usr/bin/ld: null/alienarena_ded-cl_null.o:./source/./game/q_shared.h:264: multiple definition of `com_parseLine'; game/alienarena_ded-q_shared.o:./source/game/q_shared.h:264: first defined here
/usr/bin/ld: qcommon/alienarena_ded-cmd.o:./source/qcommon/qcommon.h:745: multiple definition of `remoteserver_runspeed'; null/alienarena_ded-cl_null.o:./source/null/../qcommon/qcommon.h:745: first defined here
/usr/bin/ld: qcommon/alienarena_ded-cmd.o:./source/qcommon/qcommon.h:744: multiple definition of `remoteserver_jousting'; null/alienarena_ded-cl_null.o:./source/null/../qcommon/qcommon.h:744: first defined here
/usr/bin/ld: qcommon/alienarena_ded-cmd.o:./source/./game/q_shared.h:264: multiple definition of `com_parseLine'; game/alienarena_ded-q_shared.o:./source/game/q_shared.h:264: first defined here
/usr/bin/ld: qcommon/alienarena_ded-cmodel.o:./source/qcommon/qcommon.h:745: multiple definition of `remoteserver_runspeed'; null/alienarena_ded-cl_null.o:./source/null/../qcommon/qcommon.h:745: first defined here
/usr/bin/ld: qcommon/alienarena_ded-cmodel.o:./source/qcommon/qcommon.h:744: multiple definition of `remoteserver_jousting'; null/alienarena_ded-cl_null.o:./source/null/../qcommon/qcommon.h:744: first defined here
/usr/bin/ld: qcommon/alienarena_ded-cmodel.o:./source/./game/q_shared.h:264: multiple definition of `com_parseLine'; game/alienarena_ded-q_shared.o:./source/game/q_shared.h:264: first defined here
/usr/bin/ld: qcommon/alienarena_ded-common.o:./source/qcommon/qcommon.h:745: multiple definition of `remoteserver_runspeed'; null/alienarena_ded-cl_null.o:./source/null/../qcommon/qcommon.h:745: first defined here
/usr/bin/ld: qcommon/alienarena_ded-common.o:./source/qcommon/qcommon.h:744: multiple definition of `remoteserver_jousting'; null/alienarena_ded-cl_null.o:./source/null/../qcommon/qcommon.h:744: first defined here
/usr/bin/ld: qcommon/alienarena_ded-common.o:./source/./game/q_shared.h:264: multiple definition of `com_parseLine'; game/alienarena_ded-q_shared.o:./source/game/q_shared.h:264: first defined here
[...]

More information about the corresponding GCC change can be found here:
https://gcc.gnu.org/gcc-10/porting_to.html
"Default to -fno-common"


Andreas