[clang] [C++20][Modules] Fix incomplete decl chains (PR #129982)

[Michael Park via cfe-commits]

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@@ -10178,12 +10178,12 @@ void ASTReader::visitTopLevelModuleMaps(
 }
 
 void ASTReader::finishPendingActions() {
-  while (
-      !PendingIdentifierInfos.empty() || !PendingDeducedFunctionTypes.empty() ||
-      !PendingDeducedVarTypes.empty() || !PendingIncompleteDeclChains.empty() ||
-      !PendingDeclChains.empty() || !PendingMacroIDs.empty() ||
-      !PendingDeclContextInfos.empty() || !PendingUpdateRecords.empty() ||
-      !PendingObjCExtensionIvarRedeclarations.empty()) {
+  while (!PendingIdentifierInfos.empty() ||
+         !PendingDeducedFunctionTypes.empty() ||
+         !PendingDeducedVarTypes.empty() || !PendingDeclChains.empty() ||
+         !PendingMacroIDs.empty() || !PendingDeclContextInfos.empty() ||
+         !PendingUpdateRecords.empty() ||
+         !PendingObjCExtensionIvarRedeclarations.empty()) {
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mpark wrote:

This is the effect of reapplying #121245, which moved `PendingIncompleteDeclChains` out of this loop.

https://github.com/llvm/llvm-project/pull/129982