[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 +1,410 @@
+# 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 category names for swift -- in order to not crash
+# RUN: llvm-mc -filetype=obj -triple=arm64-apple-macos -o cat_swift.o %s
+# RUN: %lld -arch arm64 -dylib -o cat_swift.dylib cat_swift.o -objc_category_merging
+# RUN: llvm-objdump --objc-meta-data --macho cat_swift.dylib | FileCheck %s --check-prefixes=CHECK-MERGE
+
+; CHECK-MERGE: Contents of (__DATA_CONST,__objc_classlist) section
+; CHECK-MERGE: _$s11SimpleClassAACN
----------------
thevinster wrote:

```suggestion
; CHECK-MERGE-NEXT: _$s11SimpleClassAACN
```

If these are all consecutive, practice is to use `-NEXT` here and the rest below.

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