[lld] [lld-macho] Category Merger: add support for addrsig references (PR #90903)

[via llvm-commits]

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@@ -478,6 +482,8 @@ class ObjcCategoryMerger {
   std::vector<ConcatInputSection *> &allInputSections;
   // Map of base class Symbol to list of InfoInputCategory's for it
   DenseMap<const Symbol *, std::vector<InfoInputCategory>> categoryMap;
+  // Set for tracking InputSection erased via eraseISec
+  std::unordered_set<InputSection *> erasedIsecs;
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alx32 wrote:

I see the point in set vs sorted array, but here a hashset is the better approach (`unordered_set`). It has better lookup time than binary search and we need that looking up lots of reloc's. 

https://github.com/llvm/llvm-project/pull/90903