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

[Ellis Hoag via llvm-commits]

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@@ -1188,6 +1200,36 @@ void ObjcCategoryMerger::eraseMergedCategories() {
                                   catLayout.instancePropsOffset);
     }
   }
+
+  removeRefsToErasedIsecs();
+}
+
+// The compiler may generate references to categories inside the addrsig
+// section. This function will erase these references.
+void ObjcCategoryMerger::removeRefsToErasedIsecs() {
+  for (InputSection *isec : inputSections) {
+    if (isec->getName() != section_names::addrSig)
+      continue;
+
+    auto &_erasedIsecs = erasedIsecs;
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ellishg wrote:

I'm not sure I understand why we need a copy here. Does this not work if we use `erasedIsecs` directly?

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