[Bug ipa/115237] -Wsuggest-attribute=pure false positive for obviously non-pure function

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115237

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |hubicka at gcc dot gnu.org,
                   |                            |rguenth at gcc dot gnu.org
           Keywords|                            |diagnostic

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
'pure' means the function has no side-effect besides reading global memory
_when it returns_, so it's valid to turn

 x = unite (5, 6);
 y = unite (5, 6);

into

 x = unite (5, 6);
 y = x;

at least that's my understanding.  Honza might want to clarify here.