[clang] [Clang] Ensure compound requirements do not contain placeholder expressions (PR #162618)

[Younan Zhang via cfe-commits]

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@@ -3200,6 +3200,8 @@ ExprResult Parser::ParseRequiresExpression() {
         BalancedDelimiterTracker ExprBraces(*this, tok::l_brace);
         ExprBraces.consumeOpen();
         ExprResult Expression = ParseExpression();
+        if (Expression.isUsable())
+          Expression = Actions.CheckPlaceholderExpr(Expression.get());
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zyn0217 wrote:

I see, thanks!

https://github.com/llvm/llvm-project/pull/162618