[llvm] [llvm-objcopy] Add --compress-sections (PR #85036)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,32 @@
+## Disallow (de)compression for sections within a segment as they are
+## effectively immutable.
+# RUN: rm -rf %t && mkdir %t && cd %t
+# RUN: yaml2obj %s -o a
+# RUN: not llvm-objcopy a /dev/null --compress-sections .text=zlib --compress-sections foo=none 2>&1 | FileCheck %s
+
+# CHECK: error: 'a': section '.text' within a segment cannot be (de)compressed
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MaskRay wrote:

Split

https://github.com/llvm/llvm-project/pull/85036