Vista's market share (1.77%) is a fraction of XP's (9.03%), so it's not that weird to drop support for it as well.

Reference: ttps://en.wikipedia.org/wiki/Usage_share_of_operating_systems#Desktop_and_laptop_computers

Just want to add, that Wikipedia article uses statcounter as the source. If you look at statcounter China is throwing off the data, it is running XP at 30%(!) Vs. USA @ 4.3%, UK @ 3.18%, France @ 4.8%, Australia+NZ @ 2.67-2.85%, Japan @ 3%, et al.

My point is, that 10% figure is misleading. China is higher, everyone else is lower.

Yeah though good luck finding a pure Chrome install in China anyway. Most of it runs this repackaged monstrosity: https://en.wikipedia.org/wiki/360_Secure_Browser

Sure, XP usage might be lower than reported in these figures, but Vista will have a lower market share still.

Yeah. They say Microsoft won't provide "active support," so maybe that's why Vista is not included?

It's probably mainly because Vista has a relatively low market share: probably lower than XP. It's thus not worth supporting as the earliest version of Windows they support.

Edit: Just checked. Windows XP lost non-extended support in 2009, whereas Vista lost it in 2012.

To be fair, that's "extended support," not "mainstream support" - it's mostly just security updates and so on.

Security fixes is the key part of support, to be fair. As long as a platform is getting security fixes, it's supported. But I imagine the user share on Vista is very low, it had nowhere near the level of adoption of XP or 7.

I think people misperceive "security fixes" as a binary thing when it's really a sliding scale. The choice to backport is often not a clearcut decision, and you need to balance the risk of the underlying issue against the potential conflicts with a legacy platform and its dependencies. Otherwise, your security update might cause quite a bit of collateral damage. So, Microsoft is understandably cautious and afaict backports only fixes for major issues.

Of course, that gets complicated when you consider something like Chrome's sandbox, which can depend on system guarantees that Microsoft may consider esoteric or just low-priority. To their credit, Microsoft is responsive when we find these kinds of issues and report them. However, it's not uncommon for the issues to not be considered important enough to backport to legacy OSes (or for the task to just be too arduous). That's why we also tend to focus our work on the most current supported versions, which also offer increasingly better mitigation technologies with each release.

IIRC Clang on Windows also announced a similar thing (supporting only Win 7+) maybe they plan on building it with Clang on all platforms and it's a result of that.

Maybe I misunderstood, but do you really think they would be compiling Chrome on Windows XP? I doubt that's the reason.

I think that Clang generated binaries won't run on Windows versions below 7, if I remember correctly it has something to do with implementing SEH but I could be completely wrong and it could also have nothing to do with their decision but it makes sense - they moved to clang for compiling Linux binaries to simplify build process and they are a big driver behind Clang on Windows.

I'd be very surprised to hear this. Clang and Rust both use LLVM, and Rust can generate binaries for XP (with a few caveats). Of course, the fact that LLVM no longer supports running on XP means that the Rust compiler itself doesn't run on XP (not that it ever did).

I think he meant that clang won't be targeting XP systems anymore, even when cross compilling.

I am, too. We moved machines that couldn't jump to Windows 7 to Vista to buy more time.