[Bug c/46619] gcc thinks line of code can be removed.

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46619

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |RESOLVED
         Resolution|                            |INVALID

--- Comment #8 from Andrew Pinski <pinskia at gcc dot gnu.org> 2010-11-23 
19:19:49 UTC ---
v_bignum.c:772: warning: assuming signed overflow does not occur when
simplifying conditional to constant


typedef unsigned short VBigDig;
   uv = x[1 + j] * x[1 + i];
   high = (uv & 0x80000000u) != 0;

Is really
   uv = (int)x[1 + j] * (int)x[1 + i];
   high = (uv & 0x80000000u) != 0;

So overflow is undefined.