False positive -Wcomma with static_cast<void> of dependent expression

Hello list,

The following code generates one false positive of the -Wcomma
warning: (tested with clang trunk via Matt Godbolt's Compiler

template <typename T>
void foo()
    (void)42, 0; // ok
    static_cast<void>(42), 0; // ok

    (void)T{}, 0; // ok
    static_cast<void>(T{}), 0; // false positive

The warning ignores comma expressions where the LHS is a CastExpr with
a CastKind of CK_ToVoid, but the expression static_cast<void>(T{}) has
a CastKind of CK_Dependent (confirmed with Compiler Explorer's AST

I came across this when trying to do the "expander trick" without a
fold expression or C-style cast, as in


Please open a bug report instead.

Best Jonas