[clang] [Driver] Ensure ToolChain::LibraryPaths is not empty for non-Darwin (PR #87866)

[Nico Weber via cfe-commits]

nico wrote:

I now did build clang at ccdebbae4d77 and ccdebbae4d77^. ccdebbae4d77 has `/DEFAULTLIB:clang_rt.profile.lib` in its output, ccdebbae4d77^ has /DEFAULTLIB:clang_rt.profile-x86_64.lib`. So definitely due to this change.

It sounds like you're saying that's not intentional?

(It's kind of what #81037 looks like to me – it used to default to old-style, now it defaults to "new"-style. But without this chang here, #81037 doesn't have that effect.)

https://github.com/llvm/llvm-project/pull/87866