[Bug c++/95772] warning desired when default operator= cannot be constructued

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95772

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Marc Pawlowsky from comment #0)
> I expected a diagnostic saying that operator= cannot be defaulted which is
> seen if the ASSIGN code is enabled.  The code compiles cleanly.

As expected. The C++ standard is clear about what this code means. The
explicitly defaulted assignment operator is defined as deleted, because it
would be ill-formed.

Defaulting it doesn't mean it will be provided by the compiler.


> When I wrote this bug in a large code base  with -03 and -flto the code will
> fail with illegal instructions and other memory corruption errors.  No
> problem without optimization.

What bug? The type is not assignable, how can that fail at runtime?