Thought now would be a good time to decide on upgrading manylinux for the 1.19 release so that we can make sure that everything works as expected. The choices are
-- CentOS 5, currently used, gcc 4.2 (in practice 4.5), only supports i686, x86_64.
-- CentOS 7, gcc 4.8, supports many more architectures.
The main advantage of manylinux2014 is that it supports many new architectures, some of which we are already testing against. The main disadvantage is that it requires pip >= 19.x, which may not be much of a problem 4 months from now but will undoubtedly cause some installation problems. Unfortunately, the compiler remains archaic, but folks interested in performance should be using a performance oriented distribution or compiling for their native architecture.