[llvm] Give a warning when no dwo files are provided (PR #94336)

[David Blaikie via llvm-commits]

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@@ -0,0 +1,9 @@
+; RUN: rm -rf %t && mkdir -p %t && split-file %s %t && cd %t
+; RUN: clang -g -gdwarf-4 %t/non_split.c -o %t/non_split.o
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dwblaikie wrote:

We can't run clang as part of llvm's tests (it's a layering violation - clang depends on llvm, not the other way around).

This test should contain something more basic - perhaps an empty or trivial assembly file that `llvm-mc -g` could be used to compile to an object file and that might be enough for the situation?

https://github.com/llvm/llvm-project/pull/94336