[Bug c++/85557] Incorrect calculation of function arguments with C++17 sequencing rules

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85557

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |wrong-code
             Status|WAITING                     |NEW

--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
"The initialization of a parameter, including every associated value
computation and side effect, is indeterminately sequenced with respect to that
of any other parameter."

That's indeterminately sequenced, not unsequenced:

"Evaluations A and B are indeterminately sequenced when either A is sequenced
before B or B is sequenced before A, but it is unspecified which. [ Note:
Indeterminately sequenced evaluations cannot overlap, but either could
be executed first. — end note ]"

So the function is called as foo(1, 2), but it's unspecified whether i==1 or
i==2 afterwards.