[llvm] [llvm-rc] Accept filenames provided as multiple string literals (PR #68881)

[Martin Storsjö via llvm-commits]

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+100 ICON "subdir" "/icon-new.ico"
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mstorsjo wrote:

Oh, interesting concept! Anyway, I don't think there's enough added value to complicate the testing setup here, even if it would show the intended test case clearer. I guess I could add a comment in either the `.test` or `.rc` to explain clearer what scenario the test replicates.

(We already have a few tests of llvm-rc in clang, to showcase how it successfully manages to call the preprocessor there though, but I wouldn't go so far as to place the testcase for this feature on the clang side, for the sake of keeping tests small and localized.)

https://github.com/llvm/llvm-project/pull/68881