[Bug c/91526] Unnecessary SSE and other instructions generated when compiling in C mode (vs. C++ mode)

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91526

--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> ---
Oh, and then, since we vectorized things, we do not NRV because

                 || DECL_ALIGN (found) > DECL_ALIGN (result)

thus we adjusted the VAR_DECLs alignment but the ABI says the return slot
isn't appropriately aligned (well, we do not end up returning in memory,
but...).