[clang] [clang] Fix comma location tracking inside ParenListExpr. (PR #199411)

[Erich Keane via cfe-commits]

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@@ -748,9 +748,17 @@ void ASTStmtReader::VisitParenListExpr(ParenListExpr *E) {
   unsigned NumExprs = Record.readInt();
   assert((NumExprs == E->getNumExprs()) && "Wrong NumExprs!");
   for (unsigned I = 0; I != NumExprs; ++I)
-    E->getTrailingObjects()[I] = Record.readSubStmt();
+    E->getTrailingObjects<Stmt *>()[I] = Record.readSubStmt();
   E->LParenLoc = readSourceLocation();
   E->RParenLoc = readSourceLocation();
+  if (Record.getIdx() < Record.size()) {
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erichkeane wrote:

This check very much apperas to be a smell.  We shouldn't be checking the record size/location during serialization, this shows me that we have SOME sort of mismatch that you're trying to work around.

https://github.com/llvm/llvm-project/pull/199411