Q_DECLARE_PRIVATE gets used in the declaration of the public class,
where the private class is typically visible only as a forward-decl,
with no knowledge of what it's based on; consequently, the macro is
obliged to use reinterpret_cast<>, which is subject to warnings when
the compiler *can* see both types and their alignments differ. The
same applies to Q_DECLARE_PRIVATE_D.
So suppress gcc's -Wcast-align around the d_func() return statements.
(If we get similar problems with other compilers we can add their
suppressions likewise; but, for now, we've only seen this on MIPS64,
where we use gcc.) This tripped over one use of Q_DECLARE_PRIVATE in
a private Q_SLOTS: section; for some reason, gcc didn't like the
semicolon on the friend declaration. Changing the context to plain
private fixed that.
Fixes: QTBUG-72885
Change-Id: I5edc11d46bd4eb820713adede79d53191a7e2736
Reviewed-by: Liang Qi <liang.qi@qt.io>
Reviewed-by: Ville Voutilainen <ville.voutilainen@qt.io>
Reviewed-by: Boxiang Sun <daetalusun@gmail.com>
2ab139596d