[Bug tree-optimization/105651] [12/13 Regression] bogus "may overlap" memcpy warning with std::string and operator+ at -O3

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105651

--- Comment #19 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Jason Merrill from comment #17)
> Created attachment 53474 [details]
> patch to work around the issue in the library

I've posted
https://gcc.gnu.org/pipermail/gcc-patches/2022-July/598896.html
patch for this, waiting for Jon's review.