[patch] PR32901: handle assignment...(and PR34465 and PR34448)

[Aldy Hernandez]

> The patch bootstraps.  I'm still running tests, but I'm fixing an ICE it
> has encountered, so I'm not ready to commit.  I wanted to get feedback

Tests are done, and the ICE I thought I had was there before my patch;
so there are no regressions.

The patch is done, and it fixes both 34448 and 34465.

Can someone please review this for mainline?

Thanks.
Aldy