Unsigned -> float conversion

[Rob McMahon]

<munch>

Pointed out to me by someone here - what does your favourite C compiler make
of this program :

main()
{
	unsigned long u;
	double d;
	float f;

	u = ~0;
	d = u;
	f = u;
	printf("u = %lu f = %f d = %lf\n", u, f, d);
	if (d < 0) printf("d < 0\n");
	if (f < 0) printf("f < 0\n");
}

On a VAX-780 running 4.2bsd or a Sun-2 running 2.0 it gives

u = 4294967295 f = -1.000000 d = -1.000000
d < 0
f < 0

On a Gould PN6000 running UTX/32 1.2 it gives


u = 4294967295 f = -1.000000 d = 4294967295.000000
f < 0

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Rob McMahon, Computer Unit, Warwick University, Coventry CV4 7AL, England
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Rob McMahon, Computer Unit, Warwick University, Coventry CV4 7AL, England