[clang] [NFC][Clang] Fix potential dereferencing of nullptr (PR #86759)

[Tom Honermann via cfe-commits]

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@@ -289,7 +289,7 @@ class ComplexExprEmitter
                                         const BinOpInfo &Op);
 
   QualType GetHigherPrecisionFPType(QualType ElementType) {
-    const auto *CurrentBT = dyn_cast<BuiltinType>(ElementType);
+    const auto *CurrentBT = cast<BuiltinType>(ElementType);
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tahonermann wrote:

This looks fine and is consistent with other type assumptions elsewhere in the same source file.

https://github.com/llvm/llvm-project/pull/86759