Document the supported platforms

[saghul]

I'd like us to have a SUPPORTED_PLATFORMS.md file with the following content, linked from the README. This is just a starting point, let's work through it and I'll make a proper PR:

---

Supported platforms

System	Support type	Supported versions	Notes
GNU/Linux	Tier 1	Linux >= 2.6.18 with glibc >= 2.5
macOS	Tier 1	macOS >= 10.7
Windows	Tier 1	Windows >= XP SP1	MSVC 2008 and later are supported
FreeBSD	Tier 1	>= 9
AIX	Tier 2	???	Maintainer: @iwuzhere
zOS	Tier 2	???	Maintainer: @jBarz
Linux with musl	Tier 2	???
SunOS	Tier 3	???
MinGW	Tier 3	MinGW 32 (from mingw.org) and MinGW-w64
Other	Tier 3	N/A

Support types

• Tier 1: Officially supported and tested with CI. Any contributed patch MUST NOT break such systems. These are supported by @libuv/collaborators
• Tier 2: Officially supported, but not necessarily tested with CI. These systems are maintained to the best of @libuv/collaborators ability, without being a top priority.
• Tier 3: Community maintained. These systems may inadvertently break and the community and interested parties are expected to help with the maintenance.

---

This is for v1.x, I'll adjust accordingly for master / v2.x. I also took the liberty of making SunOS tier 2. Joyent should keep it in check IMHO.

[bnoordhuis]

For linux, I'd put the baseline at kernel 2.6.18 and glibc 2.5. We have centos5 bots in our CI matrix that cover that configuration.

I don't think we ever made any promises w.r.t. freebsd except latest -STABLE. I'm open to extending it to STABLE-1 because that probably covers 95% of the freebsd user base but we don't currently have fbsd9 machines in our matrix.

I'd be perfectly happy relegating solaris to tier 3. Realistically, the only user is Joyent by means of node.js, and if they can't be arsed to put in the effort, I don't see why we should either.

[saghul]

For linux, I'd put the baseline at kernel 2.6.18 and glibc 2.5. We have centos5 bots in our CI matrix that cover that configuration.

Updated.

I don't think we've never made any promises w.r.t. freebsd except latest -STABLE. I'm open to extending it to STABLE-1 because that probably covers 95% of the freebsd user base but we don't currently have fbsd9 machines in our matrix.

I set it to 9, since we support < 10 in v1.x and 9 is still supported until the end of the year.

I'd be perfectly happy relegating solaris to tier 3. Realistically, the only user is Joyent by means of node.js, and if they can't be arsed to put in the effort, I don't see why we should either.

Done.

I'll put up a PR tomorrow so it's easier to comment on.

[bnoordhuis]

Maybe mention that fbsd9 is tier 2 in that it's not tested regularly but we'll keep it in working shape until the end of the year.

[txdv]

How is the linux musl combination tested? Android?

[saghul]

@txdv Tier 2, it's not tested. It can be easily tested with any of the ubuntu bots by installing musl-tools and exporting some env variables though.

[txdv]

Is there some write up on how to do that?

[bnoordhuis]

We have an alpine/musl buildbot for node.js now. It could be extended to test libuv as well.

No android so far: nodejs/build#359

[saghul]

Is there some write up on how to do that?

Do what? Compile with musl? Copying my own notes:

First install the musl-gcc wrapper (on Debian):

apt-get install musl-tools

Now set some environment variables:

export CC=musl-gcc
export LINK=musl-gcc
export CFLAGS=-static

(in this case I think you can leave the CFLAGS out, and the resulting binary will be linked with the musl runtime library)

[saghul]

We have an alpine/musl buildbot for node.js now. It could be extended to test libuv as well.

Oh, great! I'll open an issue in nodejs/build then

[saghul]

PR: #991

[llafuente]

How about having some #ifdef magic to raise some readable errors on unsupported platform, pointing to SUPPORTED_PLATFORMS.md or libuv doc

[saghul]

Not sure we'd like that. It's possible libuv actually works in other platforms (I think HP-UX was sort-of working) so I'd rather try and if compilation fails they'll come.