[Bug target/79364] some variadic functions with an empty struct miscompiled with C++ (at least for x64 targets)

[xilun0 at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79364

--- Comment #4 from Guillaume Knispel <xilun0 at gmail dot com> ---
The dup seems to be 69846
This might also be vaguely related to 52154