🚀 go-pugleaf

Yesterday, I came across what I think is a bug in either LightSpeed
C or the transcendental functions package.

After I generate a NAN(033) (illegal argument to trig function), the
tangent function seems to stop working (returns a bad value), even
though sine and cosine continue to work properly.

My code looked something like this:

double a=1;
double b=0;
double c;

printf("%f %f %f\n",sin(PI/4),tan(0),tan(PI/4));  /* I get correct answers */
c=a/b;  /* c now is an infinity bit pattern */
printf("%f %f\n",c,sin(c)); /* outputs   INF NAN(033) */
printf("%f %f %f\n",sin(PI/4),tan(0),tan(PI/4));

For this last line, I get the correct answer for sine, but the tangents
just give question marks, e.g. the output was .7071etc. ? ?.

Why would this happen?  There is a bug somewhere, obviously.  I am using
LSC v2.01, and System 2.something (because I'm using an unenhanced 512K mac).
Is this something that has been corrected in a later system?

				Thanks
 				Ben Waldman
 
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