[clang] [clang] fix crash when casting a parenthesized unresolved template-id (PR #183633)

[Erich Keane via cfe-commits]

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@@ -21889,7 +21889,7 @@ ExprResult Sema::CheckPlaceholderExpr(Expr *E) {
     // shouldn't need to do any further diagnostic here.
     if (!E->containsErrors())
       Diag(E->getBeginLoc(), diag::err_array_section_use)
-          << cast<ArraySectionExpr>(E)->isOMPArraySection();
+          << cast<ArraySectionExpr>(E->IgnoreParens())->isOMPArraySection();
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erichkeane wrote:

I'm OK with this now, though I may have missed it: what happened when you tried to move this to the 'top'?  (just an `E = E->IgnoreParens()`?).

https://github.com/llvm/llvm-project/pull/183633