[llvm] [AMDGPU] Allow any linkage for dynlds (PR #84742)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,37 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
+; RUN: opt -S -mtriple=amdgcn-- -passes=amdgpu-lower-module-lds < %s 2>&1 | FileCheck %s
+
+; This is an extension and should be rejected by the front-end in most cases.
+; If it goes through, lower it as dynlds.
+
+ at Var0 = linkonce_odr hidden local_unnamed_addr addrspace(3) global [0 x float] undef
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arsenm wrote:

```suggestion
@Var0 = linkonce_odr hidden local_unnamed_addr addrspace(3) global [0 x float] poison
```

https://github.com/llvm/llvm-project/pull/84742