[llvm] Add symbol version support to llvm-ifs (PR #163030)

[Roland McGrath via llvm-commits]

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@@ -62,6 +64,36 @@ struct IFSSymbol {
   bool operator<(const IFSSymbol &RHS) const { return Name < RHS.Name; }
 };
 
+struct IFSVerDef {
+  std::string Name;
+  std::vector<std::string> Parents;
+};
+
+inline bool operator==(const IFSVerDef &Lhs, const IFSVerDef &Rhs) {
+  if (Lhs.Name != Rhs.Name || Lhs.Parents != Rhs.Parents)
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frobtech wrote:

The `std::tie` comparisons are a good way to go, since that matches what `= default` will do for `operator==` in C++20 and later.

https://github.com/llvm/llvm-project/pull/163030