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

[Kyungwoo Lee via llvm-commits]

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@@ -1183,26 +1193,66 @@ void ObjcCategoryMerger::eraseMergedCategories() {
   // the references to the ones we merged.
   generateCatListForNonErasedCategories(catListToErasedOffsets);
 
+  // We use erasedIsecs below to track erased sections so we can later remove
+  // references to it.
+  std::unordered_set<InputSection *> erasedIsecs;
+  erasedIsecs.reserve(categoryMap.size());
+
   // Erase the old method lists & names of the categories that were merged
   for (auto &mapEntry : categoryMap) {
     for (InfoInputCategory &catInfo : mapEntry.second) {
       if (!catInfo.wasMerged)
         continue;
 
+      erasedIsecs.insert(catInfo.catBodyIsec);
+      erasedIsecs.insert(catInfo.catListIsec);
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kyulee-com wrote:

I'm trying to follow if `erasedIsecs` is inserted when `eraseISec` is called. So, is this line expected?

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