[Bug tree-optimization/126194] [15/16/17 Regression] LTO/DSE removes temporary initialization observed by placement delete cleanup

[rguenth at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126194

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
           Priority|P3                          |P2
   Last reconfirmed|                            |2026-07-10
     Ever confirmed|0                           |1
           Keywords|needs-bisection             |

--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> ---
r11-3386-g9e64f17d044767 added

+      else if (fndecl && DECL_IS_REPLACEABLE_OPERATOR_DELETE_P (fndecl))
+       ;

The idea was this is bare std::delete which just frees memory and does not
even inspect the freed memory (otherwise the above would miss call uses
as well, and that would be an additional fix).  For non-replaceable delete
operators we of course don't know any of that.