Bug#871114: widelands: FTBFS: game_settings.h:52:8: error: 'newuser.UserSettings::position' may be used uninitialized in this function [-Werror=maybe-uninitialized]

[Lucas Nussbaum]

Source: widelands
Version: 1:19+repack-3
Severity: serious
Tags: buster sid
User: debian-qa at lists.debian.org
Usertags: qa-ftbfs-20170805 qa-ftbfs
Justification: FTBFS on amd64

Hi,

During a rebuild of all packages in sid, your package failed to build on
amd64.

Relevant part (hopefully):
> cd /<<BUILDDIR>>/widelands-19+repack/obj-x86_64-linux-gnu/src/network && /usr/bin/c++   -I/<<BUILDDIR>>/widelands-19+repack/src -I/<<BUILDDIR>>/widelands-19+repack/obj-x86_64-linux-gnu/src -isystem /usr/include/SDL2 -isystem /usr/include/minizip -isystem /usr/include/GL  -g -O2 -fdebug-prefix-map=/<<BUILDDIR>>/widelands-19+repack=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 -Wdate-time -D_FORTIFY_SOURCE=2 -O3 -DNDEBUG    -std=c++11 -fext-numeric-literals -g -O3 -DNDEBUG -DNOPARACHUTE -Wall -Wpedantic -Wdeprecated-declarations -Wextra -Wformat -Wformat-nonliteral -Wformat-security -Wformat-y2k -Winit-self -Winvalid-pch -Wlogical-op -Wmissing-include-dirs -Wno-undef -Wold-style-cast -Woverlength-strings -Wpacked -Wpointer-arith -Wredundant-decls -Wsign-promo -Wsync-nand -Wtrampolines -Wundef -Wunused -Wunused-macros -Werror=format-security -Werror=return-type -Werror=shadow -Werror=uninitialized -o CMakeFiles/network.dir/network_player_settings_backend.cc.o -c /<<BUILDDIR>>/widelands-19+repack/src/network/network_player_settings_backend.cc
> In file included from /<<BUILDDIR>>/widelands-19+repack/src/network/network.h:29:0,
>                  from /<<BUILDDIR>>/widelands-19+repack/src/network/network.cc:20:
> /<<BUILDDIR>>/widelands-19+repack/src/network/network.h: In member function 'virtual const char* ProtocolException::what() const':
> /<<BUILDDIR>>/widelands-19+repack/src/base/wexception.h:63:90: warning: throw will always call terminate() [-Wterminate]
>  #define NEVER_HERE() throw WException(__FILE__, __LINE__, "Unreachable code was reached.")
>                                                                                           ^
> /<<BUILDDIR>>/widelands-19+repack/src/network/network.h:184:3: note: in expansion of macro 'NEVER_HERE'
>    NEVER_HERE();
>    ^~~~~~~~~~
> In file included from /<<BUILDDIR>>/widelands-19+repack/src/network/network.h:29:0,
>                  from /<<BUILDDIR>>/widelands-19+repack/src/network/internet_gaming.h:34,
>                  from /<<BUILDDIR>>/widelands-19+repack/src/network/internet_gaming.cc:20:
> /<<BUILDDIR>>/widelands-19+repack/src/network/network.h: In member function 'virtual const char* ProtocolException::what() const':
> /<<BUILDDIR>>/widelands-19+repack/src/base/wexception.h:63:90: warning: throw will always call terminate() [-Wterminate]
>  #define NEVER_HERE() throw WException(__FILE__, __LINE__, "Unreachable code was reached.")
>                                                                                           ^
> /<<BUILDDIR>>/widelands-19+repack/src/network/network.h:184:3: note: in expansion of macro 'NEVER_HERE'
>    NEVER_HERE();
>    ^~~~~~~~~~
> In file included from /<<BUILDDIR>>/widelands-19+repack/src/scripting/lua_errors.h:25:0,
>                  from /<<BUILDDIR>>/widelands-19+repack/src/scripting/lua_table.h:32,
>                  from /<<BUILDDIR>>/widelands-19+repack/src/logic/map_objects/tribes/tribe_basic_info.h:29,
>                  from /<<BUILDDIR>>/widelands-19+repack/src/logic/game_settings.h:28,
>                  from /<<BUILDDIR>>/widelands-19+repack/src/network/nethost.h:24,
>                  from /<<BUILDDIR>>/widelands-19+repack/src/network/nethost.cc:20:
> /<<BUILDDIR>>/widelands-19+repack/src/network/network.h: In member function 'virtual const char* ProtocolException::what() const':
> /<<BUILDDIR>>/widelands-19+repack/src/base/wexception.h:63:90: warning: throw will always call terminate() [-Wterminate]
>  #define NEVER_HERE() throw WException(__FILE__, __LINE__, "Unreachable code was reached.")
>                                                                                           ^
> /<<BUILDDIR>>/widelands-19+repack/src/network/network.h:184:3: note: in expansion of macro 'NEVER_HERE'
>    NEVER_HERE();
>    ^~~~~~~~~~
> In file included from /<<BUILDDIR>>/widelands-19+repack/src/scripting/lua_errors.h:25:0,
>                  from /<<BUILDDIR>>/widelands-19+repack/src/scripting/lua_table.h:32,
>                  from /<<BUILDDIR>>/widelands-19+repack/src/logic/map_objects/tribes/tribe_basic_info.h:29,
>                  from /<<BUILDDIR>>/widelands-19+repack/src/logic/game_settings.h:28,
>                  from /<<BUILDDIR>>/widelands-19+repack/src/network/netclient.h:25,
>                  from /<<BUILDDIR>>/widelands-19+repack/src/network/netclient.cc:20:
> /<<BUILDDIR>>/widelands-19+repack/src/network/network.h: In member function 'virtual const char* ProtocolException::what() const':
> /<<BUILDDIR>>/widelands-19+repack/src/base/wexception.h:63:90: warning: throw will always call terminate() [-Wterminate]
>  #define NEVER_HERE() throw WException(__FILE__, __LINE__, "Unreachable code was reached.")
>                                                                                           ^
> /<<BUILDDIR>>/widelands-19+repack/src/network/network.h:184:3: note: in expansion of macro 'NEVER_HERE'
>    NEVER_HERE();
>    ^~~~~~~~~~
> In file included from /<<BUILDDIR>>/widelands-19+repack/src/network/netclient.h:25:0,
>                  from /<<BUILDDIR>>/widelands-19+repack/src/network/netclient.cc:20:
> /<<BUILDDIR>>/widelands-19+repack/src/logic/game_settings.h: In member function 'void NetClient::receive_one_user(uint32_t, StreamRead&)':
> /<<BUILDDIR>>/widelands-19+repack/src/logic/game_settings.h:52:8: error: 'newuser.UserSettings::position' may be used uninitialized in this function [-Werror=maybe-uninitialized]
>  struct UserSettings {
>         ^~~~~~~~~~~~
> cc1plus: some warnings being treated as errors
> src/network/CMakeFiles/network.dir/build.make:113: recipe for target 'src/network/CMakeFiles/network.dir/netclient.cc.o' failed
> make[3]: *** [src/network/CMakeFiles/network.dir/netclient.cc.o] Error 1

The full build log is available from:
   http://aws-logs.debian.net/2017/08/05/widelands_19+repack-3_unstable.log

A list of current common problems and possible solutions is available at
http://wiki.debian.org/qa.debian.org/FTBFS . You're welcome to contribute!

About the archive rebuild: The rebuild was done on EC2 VM instances from
Amazon Web Services, using a clean, minimal and up-to-date chroot. Every
failed build was retried once to eliminate random failures.