Fix error in fdim/f for infinities

The comparison c == FP_INFINITE causes the function to return +inf as it
expects x = +inf to always be larger than y. This shortcut causes
several issues as it also returns +inf for the following cases:
 - fdim(+inf, +inf), expected (as per C99): +0.0
 - fdim(-inf, any non NaN), expected: +0.0

I don't see a reason to keep the comparison as all the infinity cases
return the correct result using just the ternary operation.
This commit is contained in:
Fabian Schriever 2020-03-10 11:24:12 +01:00 committed by Corinna Vinschen
parent a8a40ee575
commit 18b4e0e518
2 changed files with 2 additions and 8 deletions

View File

@ -49,11 +49,8 @@ ANSI C, POSIX.
double y;
#endif
{
int c = __fpclassifyd(x);
if (c == FP_NAN) return(x);
if (__fpclassifyd(x) == FP_NAN) return(x);
if (__fpclassifyd(y) == FP_NAN) return(y);
if (c == FP_INFINITE)
return HUGE_VAL;
return x > y ? x - y : 0.0;
}

View File

@ -14,11 +14,8 @@
float y;
#endif
{
int c = __fpclassifyf(x);
if (c == FP_NAN) return(x);
if (__fpclassifyf(x) == FP_NAN) return(x);
if (__fpclassifyf(y) == FP_NAN) return(y);
if (c == FP_INFINITE)
return HUGE_VALF;
return x > y ? x - y : 0.0;
}