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

[Erich Keane via cfe-commits]

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@@ -4958,33 +4958,42 @@ SourceLocation DesignatedInitUpdateExpr::getEndLoc() const {
 }
 
 ParenListExpr::ParenListExpr(SourceLocation LParenLoc, ArrayRef<Expr *> Exprs,
-                             SourceLocation RParenLoc)
+                             SourceLocation RParenLoc,
+                             ArrayRef<SourceLocation> CommaLocs)
     : Expr(ParenListExprClass, QualType(), VK_PRValue, OK_Ordinary),
-      LParenLoc(LParenLoc), RParenLoc(RParenLoc) {
+      LParenLoc(LParenLoc), RParenLoc(RParenLoc), NumCommas(CommaLocs.size()) {
+  assert((CommaLocs.empty() || CommaLocs.size() + 1 == Exprs.size()) &&
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erichkeane wrote:

Why do we need the 1st condition in this assert?  Can we have a case of no commas, but >1 expressions?

That said, this confirms to me we dont need to separately store the number of commas.

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