[clang] [llvm] [clang][CodeGen] `used` globals && the payloads for global ctors & dtors are globals (PR #93601)

[Matt Arsenault via cfe-commits]

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@@ -2922,18 +2922,19 @@ static void emitUsed(CodeGenModule &CGM, StringRef Name,
   if (List.empty())
     return;
 
+  llvm::Type *UsedPtrTy = llvm::PointerType::getUnqual(CGM.getLLVMContext());
+
   // Convert List to what ConstantArray needs.
   SmallVector<llvm::Constant*, 8> UsedArray;
   UsedArray.resize(List.size());
   for (unsigned i = 0, e = List.size(); i != e; ++i) {
-    UsedArray[i] = llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast(
-        cast<llvm::Constant>(&*List[i]), CGM.GlobalsInt8PtrTy);
+    UsedArray[i] = llvm::ConstantExpr::getPointerCast(
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arsenm wrote:

Although we should get rid of it, getPointerBitCastOrAddrSpaceCast is the correct helper for now. We should have a getAddrSpaceCast that doesn't throw a fit on same typed pointers but getPointerCast will try to insert ptrtoint etc. 

https://github.com/llvm/llvm-project/pull/93601