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| author | Joseph Myers <joseph@codesourcery.com> | 2012-03-28 14:57:58 +0000 |
|---|---|---|
| committer | Joseph Myers <joseph@codesourcery.com> | 2012-03-28 14:57:58 +0000 |
| commit | d6270972f79fe89a96fa7a3909991dad2e317033 (patch) | |
| tree | 18ed157e89359cf8711d641916028dab73e37449 /sysdeps/ieee754 | |
| parent | 414fca039edfece0dc9bfc266730e390124687de (diff) | |
| download | glibc-d6270972f79fe89a96fa7a3909991dad2e317033.tar.gz glibc-d6270972f79fe89a96fa7a3909991dad2e317033.tar.xz glibc-d6270972f79fe89a96fa7a3909991dad2e317033.zip | |
Fix pow of negative numbers to integer exponents (bugs 369, 2678, 3866).
Diffstat (limited to 'sysdeps/ieee754')
| -rw-r--r-- | sysdeps/ieee754/k_standard.c | 54 |
1 files changed, 53 insertions, 1 deletions
diff --git a/sysdeps/ieee754/k_standard.c b/sysdeps/ieee754/k_standard.c index c3326d9ef5..4e65bb16ce 100644 --- a/sysdeps/ieee754/k_standard.c +++ b/sysdeps/ieee754/k_standard.c @@ -508,6 +508,9 @@ __kernel_standard(double x, double y, int type) exc.type = UNDERFLOW; exc.name = type < 100 ? "pow" : (type < 200 ? "powf" : "powl"); exc.retval = zero; + y *= 0.5; + if (x < zero && __rint (y) != y) + exc.retval = -zero; if (_LIB_VERSION == _POSIX_) __set_errno (ERANGE); else if (!matherr(&exc)) { @@ -1004,6 +1007,8 @@ long double __kernel_standard_l (long double x, long double y, int type) { double dx, dy; + struct exception exc; + if (isfinite (x)) { long double ax = fabsl (x); @@ -1028,5 +1033,52 @@ __kernel_standard_l (long double x, long double y, int type) } else dy = y; - return __kernel_standard (dx, dy, type); + + switch (type) + { + case 221: + /* powl (x, y) overflow. */ + exc.arg1 = dx; + exc.arg2 = dy; + exc.type = OVERFLOW; + exc.name = "powl"; + if (_LIB_VERSION == _SVID_) + { + exc.retval = HUGE; + y *= 0.5; + if (x < zero && __rintl (y) != y) + exc.retval = -HUGE; + } + else + { + exc.retval = HUGE_VAL; + y *= 0.5; + if (x < zero && __rintl (y) != y) + exc.retval = -HUGE_VAL; + } + if (_LIB_VERSION == _POSIX_) + __set_errno (ERANGE); + else if (!matherr (&exc)) + __set_errno (ERANGE); + return exc.retval; + + case 222: + /* powl (x, y) underflow. */ + exc.arg1 = dx; + exc.arg2 = dy; + exc.type = UNDERFLOW; + exc.name = "powl"; + exc.retval = zero; + y *= 0.5; + if (x < zero && __rintl (y) != y) + exc.retval = -zero; + if (_LIB_VERSION == _POSIX_) + __set_errno (ERANGE); + else if (!matherr (&exc)) + __set_errno (ERANGE); + return exc.retval; + + default: + return __kernel_standard (dx, dy, type); + } } |