[llvm] [llvm-objcopy][COFF] Update WinCFGuard section contents after stripping (PR #153322)

[Evgenii Kudriashov via llvm-commits]

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@@ -92,6 +93,63 @@ Error COFFWriter::finalizeSymbolContents() {
   return Error::success();
 }
 
+Error COFFWriter::finalizeCFGuardContents() {
+  DenseMap<size_t, size_t> SymIdMap;
+  bool NeedUpdate = false;
+  for (Symbol &Sym : Obj.getMutableSymbols()) {
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e-kud wrote:

The code changed, now we collect `coff_aux_section_definition` that need to be mutable to set the checksum. We can use `const_cast` though but I hope this is not what is meant.

https://github.com/llvm/llvm-project/pull/153322