[Bug target/113269] [14 Regression] X86_64 generates extra mov (and xchg) when passing struct with constant value to function

[roger at nextmovesoftware dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113269

Roger Sayle <roger at nextmovesoftware dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2026-01-27
             Status|UNCONFIRMED                 |NEW
            Summary|X86_64 generates extra mov  |[14 Regression] X86_64
                   |(and xchg) when passing     |generates extra mov (and
                   |struct with constant value  |xchg) when passing struct
                   |to function                 |with constant value to
                   |                            |function
      Known to fail|                            |14.3.0
                 CC|                            |roger at nextmovesoftware dot 
com
      Known to work|                            |16.0
     Ever confirmed|0                           |1

--- Comment #2 from Roger Sayle <roger at nextmovesoftware dot com> ---
I can confirm that this was a regression in GCC 14.x, but was fixed/resolved in
GCC 15.x.  It would be good to identify which patch or patches would need to be
backported, to see if that makes sense.