revert undefined behavior introduction (recommended by clippy?)

[danielrh]

Hi folks
In a recent revision of rust-sdl2 my art tool ( https://github.com/danielrh/stamps ) was beginning to get increasingly difficult to track undefined behavior, especially on release.

After trying everything I knew of with the SDL 2.0.10 upgrade--I determined it was likely to be in the rust layer.
So I bisected the code and found the offending diff was a9893f0 which returned the address of a local variable when getting the raw data out of a rect

I've attached a reverting change here which restores my program to normal operations

[antonok-edm]

Wow, sorry about that! For reference (no pun intended), this is the clippy lint in question.

I hadn't looked at it too closely at the time, but it definitely doesn't make sense to get a raw pointer to a temporarily Copyed object that gets immediately dropped.

It looks like that lint has been downgraded to "pedantic" since I made that commit, but the behavior still exists - I've just opened rust-lang/rust-clippy#5953.

[Cobrand]

Nice catch, can you add something like #[allow(trivially_copy_pass_by_ref)] so that clippy does not catch this one in the future? (I have no idea if this is the right syntax for clippy). It's likely in a year or two this will get overlooked and happen again without an "allow" part.

You might want to link this issue next to it as well so that we know what it's for.

[danielrh]

ok I've updated the diff to suppress the warning in all raw() functions that return pointers.
Hopefully y'all can merge it soon and do another cargo package release--I'd like to get back on the official build

[Cobrand]

Thanks! 0.34.3 should be live now.

[danielrh]

Thank you for your swift action here!! Much appreciated