Cannot create socket for debug builds

[Zeno-]

Both minetest (client) and minetestserver throw an exception when built using Debug Build Type (Fedora 20). c.f. socket.cpp line 341

cmake /home/myhome/minetest -DENABLE_CURL=true -DENABLE_FREETYPE=true -DENABLE_LEVELDB=true -DCMAKE_BUILD_TYPE=Debug

$ ./minetest
[...snip...]
terminate called after throwing an instance of 'SocketException'
what():  Failed to create socket
Aborted (core dumped)
$ ./minetestserver 
[...snip...]
terminate called after throwing an instance of 'SocketException'
what():  Failed to create socket
Aborted (core dumped)

gcc (GCC) 4.8.3 20140624 (Red Hat 4.8.3-1)
3.15.6-200.fc20.x86_64 #1 SMP Fri Jul 18 02:36:27 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
cmake version 2.8.12.2

$ git rev-parse --verify HEAD
8979a3dd99fad05582d7308097e326b126ef0da6

Edit: last hash check was for my own fork. Same issue with official HEAD

$ git rev-parse --verify HEAD
5357a17bac1a3e4070e1529be1eaae57a48ed524

Edit2: tried cmake with no options apart from -DCMAKE_BUILD_TYPE=Debug ... same result

[Zeno-]

This is actually due to the socket unit test (which fails on systems where ipv6 is not available). I don't think that a unit test should fail due to this and have a (simple) solution but cannot test on a non-Linux OSs yet.

[ShadowNinja]

Duplicate of #793.

[kahrl]

fixed by 209c0dd