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| author | Szabolcs Nagy <szabolcs.nagy@arm.com> | 2017-10-03 17:13:18 +0100 |
|---|---|---|
| committer | Szabolcs Nagy <szabolcs.nagy@arm.com> | 2017-10-04 10:13:56 +0100 |
| commit | 8f8f8ef7aba40ef883291e4c4d95a419c3327d70 (patch) | |
| tree | 31b06c0b90a6b188783e2037e19c35e8530d3228 | |
| parent | 955774751b71c4bc94029dd541ad9d34634ec995 (diff) | |
| download | glibc-8f8f8ef7aba40ef883291e4c4d95a419c3327d70.tar glibc-8f8f8ef7aba40ef883291e4c4d95a419c3327d70.tar.gz glibc-8f8f8ef7aba40ef883291e4c4d95a419c3327d70.tar.bz2 glibc-8f8f8ef7aba40ef883291e4c4d95a419c3327d70.zip | |
[BZ #22243] fix log2(0) and log(10) in downward rounding
On 64bit targets if the SVID compat wrapper is suppressed (e.g. static linking)
then log2(0) and log10(0) returned inf instead of -inf.
[BZ #22243]
* sysdeps/ieee754/dbl-64/wordsize-64/e_log10.c (__ieee754_log10): Use fabs.
* sysdeps/ieee754/dbl-64/wordsize-64/e_log2.c (__ieee754_log2): Likewise.
| -rw-r--r-- | ChangeLog | 6 | ||||
| -rw-r--r-- | sysdeps/ieee754/dbl-64/wordsize-64/e_log10.c | 2 | ||||
| -rw-r--r-- | sysdeps/ieee754/dbl-64/wordsize-64/e_log2.c | 2 |
3 files changed, 8 insertions, 2 deletions
@@ -1,3 +1,9 @@ +2017-10-04 Szabolcs Nagy <szabolcs.nagy@arm.com> + + [BZ #22243] + * sysdeps/ieee754/dbl-64/wordsize-64/e_log10.c (__ieee754_log10): Use fabs. + * sysdeps/ieee754/dbl-64/wordsize-64/e_log2.c (__ieee754_log2): Likewise. + 2017-10-03 H.J. Lu <hongjiu.lu@intel.com> * sysdeps/i386/start.S: Replace "leal main@GOT(%ebx), %eax" with diff --git a/sysdeps/ieee754/dbl-64/wordsize-64/e_log10.c b/sysdeps/ieee754/dbl-64/wordsize-64/e_log10.c index 4f5a81669e..cd5567182f 100644 --- a/sysdeps/ieee754/dbl-64/wordsize-64/e_log10.c +++ b/sysdeps/ieee754/dbl-64/wordsize-64/e_log10.c @@ -65,7 +65,7 @@ __ieee754_log10 (double x) if (hx < INT64_C(0x0010000000000000)) { /* x < 2**-1022 */ if (__glibc_unlikely ((hx & UINT64_C(0x7fffffffffffffff)) == 0)) - return -two54 / (x - x); /* log(+-0)=-inf */ + return -two54 / fabs (x); /* log(+-0)=-inf */ if (__glibc_unlikely (hx < 0)) return (x - x) / (x - x); /* log(-#) = NaN */ k -= 54; diff --git a/sysdeps/ieee754/dbl-64/wordsize-64/e_log2.c b/sysdeps/ieee754/dbl-64/wordsize-64/e_log2.c index 5ccb78cf03..f08d5b337d 100644 --- a/sysdeps/ieee754/dbl-64/wordsize-64/e_log2.c +++ b/sysdeps/ieee754/dbl-64/wordsize-64/e_log2.c @@ -81,7 +81,7 @@ __ieee754_log2 (double x) if (hx < INT64_C(0x0010000000000000)) { /* x < 2**-1022 */ if (__glibc_unlikely ((hx & UINT64_C(0x7fffffffffffffff)) == 0)) - return -two54 / (x - x); /* log(+-0)=-inf */ + return -two54 / fabs (x); /* log(+-0)=-inf */ if (__glibc_unlikely (hx < 0)) return (x - x) / (x - x); /* log(-#) = NaN */ k -= 54; |