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From:	"Phan, Linh H (343H)" <linh DOT h DOT phan AT jpl DOT nasa DOT gov>
To:	"cygwin AT cygwin DOT com" <cygwin AT cygwin DOT com>
Date:	Sat, 19 Dec 2009 22:44:43 -0800
Subject:	wrap around problem for "double"?
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Hi,

  I was wondering why when "double" is assigned into a "short int" in cygwi=
n 1.7, it doesn't wrap around correctly, eg:

main ()=20
{
  short int x;
  int y =3D -63757;
  double y2 =3D -63757;
  x =3D y; // wraps around correctly going from int to short int
  printf("%d (should be 1779)\n",x);
  x =3D y2; // but just truncates when going from double to short int
  printf("%d (THIS DOES NOT WRAP AROUND CORRECTLY, should be 1779)\n",x);
}

The output is this:

1779 (should be 1779)
-32768 (THIS DOES NOT WRAP AROUND CORRECTLY, should be 1779)

Instead of wrapping around for the short int, it just truncates it at -3276=
8 which is not the behavior I was expecting.  It doesn't work like this eit=
her on linux or solaris operating system.  Also, when assigning a double in=
to an int, it will just truncates and not wrap around.  Is this a bug and i=
f so, is there a newer version of Cygwin that fixes this bug?

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