[llvm] [llvm-readobj,ELF] Support --decompress/-z (PR #82594)

[James Henderson via llvm-commits]

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@@ -0,0 +1,67 @@
+# REQUIRES: zlib
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jh7370 wrote:

That's fine, but one thought that did occur to me is that I suspect zlib is available on more machines than zstd, therefore by having a zstd unsupported test case, you'd be more likely to have coverage of both the supported and unsupported code paths on the same machine.

I'm okay if you still want to do it though.

https://github.com/llvm/llvm-project/pull/82594