Seems like the conversion glitch could be happening at several places.

Maybe the initial assignment of float foo needs a cast. MSVC warns about loss of precision in such cases -- maybe it's serious. :) 

float foo = (float)nv;

[download]

As a workaround, perhaps you could truncate the initial assignment of the double:

double nv = (float)(2.0 / 3);

[download]

Lastly, maybe something is awry in the conversions that are being done during the comparison -- like it's ignoring your cast. It's a stab in the dark, but maybe a hack like this would get it to pay attention: 

static __inline int
compare_truncated_double_to_float(double d, float f)
{
    float truncted_double = (float)d;
    if (f == truncated_double) { return 1; }
    else                       { return 0; }
}

[download]

PS: This is relevant to the work I do ensuring Windows compatibility for my XS distros.

--
Marvin Humphrey

In reply to Re: [Win32, C, and way OT] C floats, doubles, and their equivalence by creamygoodness
in thread [Win32, C, and way OT] C floats, doubles, and their equivalence by syphilis

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