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/* feholdexcept/feupdateenv example */
#include <stdio.h> /* printf, puts */
#include <fenv.h> /* feholdexcept, feclearexcept, fetestexcept, feupdateenv, FE_* */
#include <math.h> /* log */
#pragma STDC FENV_ACCESS on
double log_zerook (double x) {
fenv_t fe;
feholdexcept(&fe);
x=log(x);
feclearexcept (FE_OVERFLOW|FE_DIVBYZERO);
feupdateenv(&fe);
return x;
}
int main ()
{
feclearexcept (FE_ALL_EXCEPT);
printf ("log(0.0): %f\n", log_zerook(0.0));
if (!fetestexcept(FE_ALL_EXCEPT))
puts ("no exceptions raised");
return 0;
}
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