Fixes for c++20

A couple fixes to build Gaudi with C++20.

• Three-way comparison.
• Typedefs removed from std::allocator

added 1 commit

• a2bb8e2d - formatting

Compare with previous version

changed milestone to %v33r2

added lhcb-gaudi-head label

assigned to @clemenci

• [2020-06-14 00:08] Validation started with lhcb-gaudi-head#2631
• [2020-06-15 00:17] Validation started with lhcb-gaudi-head#2632
• [2020-06-16 00:12] Validation started with lhcb-gaudi-head#2633
• [2020-06-17 00:07] Validation started with lhcb-gaudi-head#2634
• [2020-06-17 02:45] Validation started with lhcb-gaudi-head#2635
• [2020-06-18 02:11] Validation started with lhcb-gaudi-head#2636

approved this merge request

merged

mentioned in commit 7127be45