Drop OS X 10.5 and 10.6 support in 6.0

[ofrobots]

Similar to #3804 proposing dropping support for Windows XP and Vista in 6.0. This would be a good time to also consider dropping support for Mac OS X 10.5 and 10.6.

• OS X 10.5 (Leopard) has been unsupported as of June 23, 2011 and OS X 10.6 (Snow Leopard) has been unsupported as of Feb 2014.
• I couldn't find any existing documentation on the minimum version of OS X we support for Node – are these even supported today?
• Chrome dropped support for OS X 10.5 a long time ago and in November 2015 announced end of support for 10.6, 10.7 and 10.8.
• I anticipate that V8 will start depending on C++11 library features going forward. On a Mac, this requires linking against libc++ which is only available from 10.7 onwards.
• Do we have some status (e.g. from npm) if there is a non-trivial number of users affected by this? Unlike Windows, I don't expect a significant number of users stuck on old versions. If the usage numbers are low for 10.7 and 10.8, we should consider if we should still continue supporting those in 6.0.

/cc @nodejs/ctc

EDIT: typos.

[rvagg]

/cc @nodejs/build we were discussing OSX CI today and talking about going for a new hosting option that may enable testing back to 10.7. atm we only test 10.10 so it's hard to say we have "official" support for anything else.

[Fishrock123]

I don't think we officially support anything besides 10.10 and 10.11 right now, so I don't see much problem in us "dropping" working functionality on < 10.7

[jbergstroem]

Can we confirm that node.js even builds on 10.5,10.6?

We might encounter issues deviating from Chrome's (upstream's) decision process, but sticking with 10.7 as long as possible (libc++) would be nice. Hopefully we'll have test coverage for this soon enough.

[mhdawson]

We build internally on 10.8 but that's as far back as we go.

[ChALkeR]

Note that everything up to 10.8 does not even receive security updates from Apple (for quite a long time, btw).

Not exactly sure about 10.9, but it also looks like it's not supported by Apple anymore (I'm talking about the secruity updates now).

10.10 and 10.11 are fine.

[ChALkeR]

Chrome dropped support for OS X 10.5 a long time ago and in November 2015 announced end of support for 10.6, 10.7 and 10.8.

Why not drop everything up to 10.8 then? As I understood it, those are not supported by Chrome, and are not supported by Apple.

[ofrobots]

@ChALkeR As I haven't seen node usage data for old Mac OS X versions, I didn't want to take a too aggressive stance in dropping support. I am comfortable asserting that we should not support <= 10.6. Based on the feedback here, this sound uncontroversial.

There might be some value in being a bit more aggressive here and dropping support for <= 10.8. The build WG has decided to test as far back as 10.7, so we should align with or adjust that decision. @jbergstroem: was there a reason 10.7 was picked?

[jbergstroem]

@ofrobots just to make it clear: 10.7 is my opinion and not representing the build group. I'm happy to have a chat with the other guys and give a slightly more formal decision. The main problem for us right now is that we don't have enough hardware/os'es to test on. If your conclusion is that 10.8 is the better option then lets have that as baseline in this discussion instead.

[mhdawson]

FYI - https://groups.google.com/forum/#!topic/v8-users/Io_bXZ2bGG4

v8 is raising minimum to 10.7 for 5.1.

I think that's a good rational for moving to 10.7 as well but does not mean we can't pick a later one like 10.8 if that makes sense.

[corbinu]

Based on a quick look at OS support for Intel Macs I would recommend 10.7 as it seems every mac that can run 10.8 can be upgraded to 10.11

So 10.7 is the most likely case for a user being excluded by their hardware.

[jbergstroem]

Libuv is gunning for 10.7 as well: libuv/libuv#758

[rvagg]

+1 on 10.7 onward then, but do we actually need to document this anywhere? afaik we don't maintain an official list, but we probably should do .. maybe this is something @nodejs/build should maintain.

[jbergstroem]

I'd preferably want to avoid taking this decision until we're actually testing OS X properly, but thats unrealistic in the near future.

@rvagg: Yeah, might be time to revamp a supported os/toolchain list (as well as "known to work" which we with enough maturity/test coverage can grow into supported). That likely belongs with the @nodejs/build group.