Error building ROOT 6.26/10 on Win11 with VS17

[bellenot]

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Install ROOT v6.26 from source on Windows 11 does not populate install dir

OK, now I see what the issue is.This is an incompatibility between Visual Studio v17.4 and LLVM 9.0. To solve this, you have to either build the master branch (from github, see Building ROOT from source - ROOT) or wait for ROOT v6.28/00, which will come early next year. And note you can also take a pre-built binary