[lld] [lld-macho] Category merger: handle addends when getting symbol at offset (PR #91238)

[Vincent Lee via llvm-commits]

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@@ -0,0 +1,357 @@
+# REQUIRES: aarch64
+# RUN: rm -rf %t; mkdir %t && cd %t
+
+############ Test merging multiple categories into a single category ############
+## Apply category merging to swiftc code just make sure we can handle addends
+## and don't erase cateogry names for swift -- in order to not crash
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thevinster wrote:

```suggestion
## and don't erase category names for swift -- in order to not crash
```

https://github.com/llvm/llvm-project/pull/91238