[clang] [clang] Fix -Wdouble-promotion in C++ list-initialization (PR #159992)

[via cfe-commits]

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@@ -12797,6 +12797,22 @@ static void CheckCommaOperand(
     S.CheckImplicitConversion(E, T, CC);
 }
 
+static Expr *IgnoreExplicitCastForImplicitConversionCheck(ExplicitCastExpr *E) {
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Sirraide wrote:

Also, looking at this, can you add some tests for `double{{f}}` and `double{(f)}`; I’d expect both of these to just work (in the former case we still only have a single `InitListExpr`).

https://github.com/llvm/llvm-project/pull/159992