Displaying 1 result from an estimated 1 matches for "sexact".
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2016 Aug 18
5
fenv.h vs the optimizer
...;, rint(0.5));
fesetround(FE_UPWARD);
printf("foo upward: %f\n", rint(0.5));
}
If compiled with optimization, only one call to rint() is made and the
result is reused.
void bar(double a, double b) {
feclearexcept(FE_INEXACT);
a / b;
printf("bar %f / %f is %sexact\n", a, b, fetestexcept(FE_INEXACT)?
"in": "");
}
The compiler omits the divide as the result is unused. And so on.
Presumably this has never worked? And perhaps LLVM is no worse than
other compilers in this regard?
Is there any appetite to fix it? What kind of chang...