[lld] [LLD][COFF] Avoid forcing lazy symbols in loadMinGWSymbols during symbol table enumeration (PR #141593)

[Martin Storsjö via llvm-commits]

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@@ -245,14 +245,23 @@ void SymbolTable::reportUndefinedSymbol(const UndefinedDiag &undefDiag) {
 }
 
 void SymbolTable::loadMinGWSymbols() {
+  std::vector<Symbol *> undefs;
   for (auto &i : symMap) {
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mstorsjo wrote:

So the problem we're fixing here is that we avoid mutating `symMap` while iterating over it?

https://github.com/llvm/llvm-project/pull/141593