[Bug tree-optimization/78218] [7 Regression] wrong code at -Os and above on x86_64-linux-gnu (in both 32-bit and 64-bit modes)

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78218

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |rguenth at gcc dot 
gnu.org

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
Indeed.

   <bb 2>:
-  a[1].v = 1;
   a[0] = a[1];
-  a[1].v = 0;
+  MEM[(int *)&a + 4B] = 0;

it misses the use of a[1] in a[0] = a[1]

I have a patch.