Fix compilation with gcc 5.4 (Ubuntu 16.04)

Although we do not officially support Ubuntu 16.04, it's nice to keep it working.

It was broken by !579 (merged).

CC: @ishapova @graven

• [2018-02-14 15:38] Validation started with lhcb-gaudi-merge#415
• [2018-02-15 00:05] Validation started with lhcb-gaudi-head-py3#65
• [2018-02-15 00:06] Validation started with lhcb-tdr-test#60
• [2018-02-15 00:08] Validation started with lhcb-gaudi-head#1769
• [2018-02-16 00:04] Validation started with lhcb-gaudi-head-py3#66
• [2018-02-16 00:04] Validation started with lhcb-tdr-test#61
• [2018-02-16 00:06] Validation started with lhcb-gaudi-head#1770
• [2018-02-17 00:03] Validation started with lhcb-gaudi-head-py3#67
• [2018-02-17 00:05] Validation started with lhcb-tdr-test#62
• [2018-02-17 00:13] Validation started with lhcb-gaudi-head#1771
• [2018-02-18 00:03] Validation started with lhcb-gaudi-head-py3#68
• [2018-02-18 00:06] Validation started with lhcb-tdr-test#63
• [2018-02-18 00:08] Validation started with lhcb-gaudi-head#1772
• [2018-02-18 00:47] Validation started with lhcb-tdr-test#63
• [2018-02-18 00:49] Validation started with lhcb-gaudi-head-py3#68
• [2018-02-18 01:03] Validation started with lhcb-gaudi-head#1772
• [2018-02-18 01:26] Validation started with lhcb-tdr-test#63
• [2018-02-18 01:45] Validation started with lhcb-gaudi-head-py3#68
• [2018-02-18 01:47] Validation started with lhcb-gaudi-head#1772
• [2018-02-19 00:03] Validation started with lhcb-gaudi-head-py3#69
• [2018-02-19 00:05] Validation started with lhcb-tdr-test#64
• [2018-02-19 00:13] Validation started with lhcb-gaudi-head#1773
• [2018-02-19 08:14] Validation started with lhcb-gaudi-head#1774
• [2018-02-20 00:04] Validation started with lhcb-gaudi-head-py3#70
• [2018-02-20 00:07] Validation started with lhcb-tdr-test#65
• [2018-02-20 00:10] Validation started with lhcb-gaudi-head#1775
• [2018-02-21 00:03] Validation started with lhcb-gaudi-head-py3#71
• [2018-02-21 00:07] Validation started with lhcb-tdr-test#66
• [2018-02-21 00:08] Validation started with lhcb-gaudi-head#1776
• [2018-02-22 01:03] Validation started with lhcb-gaudi-head-py3#72
• [2018-02-22 01:07] Validation started with lhcb-tdr-test#67
• [2018-02-22 01:08] Validation started with lhcb-gaudi-head#1777
• [2018-02-23 01:03] Validation started with lhcb-gaudi-head-py3#73
• [2018-02-23 01:06] Validation started with lhcb-tdr-test#68
• [2018-02-23 01:09] Validation started with lhcb-gaudi-head#1778
• [2018-02-24 01:03] Validation started with lhcb-gaudi-head-py3#74
• [2018-02-24 01:10] Validation started with lhcb-gaudi-head#1779
• [2018-02-24 01:15] Validation started with lhcb-tdr-test#69
• [2018-02-25 01:04] Validation started with lhcb-gaudi-head-py3#75
• [2018-02-25 01:06] Validation started with lhcb-tdr-test#70
• [2018-02-25 01:08] Validation started with lhcb-gaudi-head#1780
• [2018-02-26 01:03] Validation started with lhcb-gaudi-head-py3#76
• [2018-02-26 01:06] Validation started with lhcb-tdr-test#71
• [2018-02-26 01:09] Validation started with lhcb-gaudi-head#1781
• [2018-02-27 01:03] Validation started with lhcb-gaudi-head-py3#77
• [2018-02-27 01:07] Validation started with lhcb-tdr-test#72
• [2018-02-27 01:11] Validation started with lhcb-gaudi-head#1782
• [2018-02-28 01:03] Validation started with lhcb-gaudi-head-py3#78
• [2018-02-28 01:06] Validation started with lhcb-tdr-test#73
• [2018-02-28 01:12] Validation started with lhcb-gaudi-head#1783
• [2018-03-01 00:03] Validation started with lhcb-gaudi-head-py3#79
• [2018-03-01 00:05] Validation started with lhcb-tdr-test#74
• [2018-03-01 00:12] Validation started with lhcb-gaudi-head#1784
• [2018-03-01 13:05] Validation started with lhcb-upgrade-hackathon#40
• [2018-03-02 00:05] Validation started with lhcb-gaudi-head-py3#80
• [2018-03-02 00:05] Validation started with lhcb-upgrade-hackathon#41
• [2018-03-02 00:06] Validation started with lhcb-tdr-test#75
• [2018-03-02 00:09] Validation started with lhcb-gaudi-head#1785
• [2018-03-02 09:45] Validation started with lhcb-upgrade-hackathon#42
• [2018-03-03 00:03] Validation started with lhcb-gaudi-head-py3#81
• [2018-03-03 00:04] Validation started with lhcb-upgrade-hackathon#43
• [2018-03-03 00:05] Validation started with lhcb-tdr-test#76
• [2018-03-03 00:10] Validation started with lhcb-gaudi-head#1786
• [2018-03-03 09:56] Validation started with lhcb-gaudi-head#1787
• [2018-03-04 00:04] Validation started with lhcb-upgrade-hackathon#44
• [2018-03-04 00:05] Validation started with lhcb-gaudi-head-py3#82
• [2018-03-04 00:05] Validation started with lhcb-tdr-test#77
• [2018-03-04 00:06] Validation started with lhcb-gaudi-head#1788
• [2018-03-05 00:04] Validation started with lhcb-gaudi-head-py3#83
• [2018-03-05 00:08] Validation started with lhcb-upgrade-hackathon#45
• [2018-03-05 00:10] Validation started with lhcb-gaudi-head#1789
• [2018-03-05 00:10] Validation started with lhcb-tdr-test#78
• [2018-03-06 00:03] Validation started with lhcb-gaudi-head-py3#84
• [2018-03-06 00:03] Validation started with lhcb-upgrade-hackathon#46
• [2018-03-06 00:06] Validation started with lhcb-tdr-test#79
• [2018-03-06 00:08] Validation started with lhcb-gaudi-head#1790
• [2018-03-07 00:05] Validation started with lhcb-gaudi-head-py3#85
• [2018-03-07 00:05] Validation started with lhcb-upgrade-hackathon#47
• [2018-03-07 00:06] Validation started with lhcb-tdr-test#80
• [2018-03-07 00:13] Validation started with lhcb-gaudi-head#1791
• [2018-03-07 14:24] Validation started with lhcb-tdr-test#81
• [2018-03-08 00:04] Validation started with lhcb-upgrade-hackathon#48
• [2018-03-08 00:04] Validation started with lhcb-gaudi-head-py3#86
• [2018-03-08 00:06] Validation started with lhcb-tdr-test#82
• [2018-03-08 00:10] Validation started with lhcb-gaudi-head#1792
• [2018-03-09 00:05] Validation started with lhcb-gaudi-head-py3#87
• [2018-03-09 00:07] Validation started with lhcb-upgrade-hackathon#49
• [2018-03-09 00:08] Validation started with lhcb-tdr-test#83
• [2018-03-09 00:10] Validation started with lhcb-gaudi-head#1793
• [2018-03-10 00:04] Validation started with lhcb-upgrade-hackathon#50
• [2018-03-10 00:06] Validation started with lhcb-gaudi-head-py3#88
• [2018-03-10 00:08] Validation started with lhcb-tdr-test#84
• [2018-03-10 00:11] Validation started with lhcb-gaudi-head#1794
• [2018-03-10 00:46] Validation started with lhcb-tdr-test#84
• [2018-03-11 00:04] Validation started with lhcb-upgrade-hackathon#51
• [2018-03-11 00:06] Validation started with lhcb-gaudi-head-py3#89
• [2018-03-11 00:07] Validation started with lhcb-tdr-test#85
• [2018-03-11 00:11] Validation started with lhcb-gaudi-head#1795
• [2018-03-12 00:05] Validation started with lhcb-gaudi-head-py3#90
• [2018-03-12 00:06] Validation started with lhcb-upgrade-hackathon#52
• [2018-03-12 00:07] Validation started with lhcb-tdr-test#86
• [2018-03-12 00:15] Validation started with lhcb-gaudi-head#1796
• [2018-03-13 00:05] Validation started with lhcb-gaudi-head-py3#91
• [2018-03-13 00:06] Validation started with lhcb-upgrade-hackathon#53
• [2018-03-13 00:09] Validation started with lhcb-tdr-test#87
• [2018-03-13 00:10] Validation started with lhcb-gaudi-head#1797
• [2018-03-14 00:04] Validation started with lhcb-gaudi-head-py3#92
• [2018-03-14 00:04] Validation started with lhcb-upgrade-hackathon#54
• [2018-03-14 00:09] Validation started with lhcb-tdr-test#88
• [2018-03-14 00:10] Validation started with lhcb-gaudi-head#1798
• [2018-03-15 00:04] Validation started with lhcb-gaudi-head-py3#93
• [2018-03-15 00:07] Validation started with lhcb-tdr-test#89
• [2018-03-15 00:19] Validation started with lhcb-gaudi-head#1799
• [2018-03-16 00:05] Validation started with lhcb-gaudi-head-py3#94
• [2018-03-16 00:06] Validation started with lhcb-tdr-test#90
• [2018-03-16 00:07] Validation started with lhcb-gaudi-head#1800
• [2018-03-16 08:02] Validation started with lhcb-gaudi-head#1801

changed the description

approved this merge request

mentioned in merge request !612 (merged)

merged

mentioned in commit 0025fd44