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| author | Joseph Myers <joseph@codesourcery.com> | 2015-08-07 23:10:35 +0000 |
|---|---|---|
| committer | Joseph Myers <joseph@codesourcery.com> | 2015-08-07 23:10:35 +0000 |
| commit | 37550cb3d6591a8f443467707ec80b4ab5c2e157 (patch) | |
| tree | 934ef1da0ab3a2cd9d0a23b1645392914e95afcc /sysdeps/ieee754/dbl-64 | |
| parent | db2bcbcb631f1c1aa023ef9f23a968e1ac288423 (diff) | |
| download | glibc-37550cb3d6591a8f443467707ec80b4ab5c2e157.zip glibc-37550cb3d6591a8f443467707ec80b4ab5c2e157.tar.gz glibc-37550cb3d6591a8f443467707ec80b4ab5c2e157.tar.bz2 | |
Fix tan missing underflows (bug 16517).
Similar to various other bugs in this area, some tan implementations
do not raise the underflow exception for subnormal arguments, when the
result is tiny and inexact. This patch forces the exception in a
similar way to previous fixes.
Tested for x86_64, x86, mips64 and powerpc.
[BZ #16517]
* sysdeps/ieee754/dbl-64/s_tan.c: Include <float.h>.
(tan): Force underflow exception for arguments with small absolute
value.
* sysdeps/ieee754/flt-32/k_tanf.c: Include <float.h>.
(__kernel_tanf): Force underflow exception for arguments with
small absolute value.
* sysdeps/ieee754/ldbl-128/k_tanl.c: Include <float.h>.
(__kernel_tanl): Force underflow exception for arguments with
small absolute value.
* sysdeps/ieee754/ldbl-128ibm/k_tanl.c: Include <float.h>.
(__kernel_tanl): Force underflow exception for arguments with
small absolute value.
* sysdeps/ieee754/ldbl-96/k_tanl.c: Include <float.h>.
(__kernel_tanl): Force underflow exception for arguments with
small absolute value.
* math/auto-libm-test-in: Add more tests of tan.
* math/auto-libm-test-out: Regenerated.
Diffstat (limited to 'sysdeps/ieee754/dbl-64')
| -rw-r--r-- | sysdeps/ieee754/dbl-64/s_tan.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_tan.c b/sysdeps/ieee754/dbl-64/s_tan.c index dcb4aca..b4e3bd2 100644 --- a/sysdeps/ieee754/dbl-64/s_tan.c +++ b/sysdeps/ieee754/dbl-64/s_tan.c @@ -34,6 +34,7 @@ /*********************************************************************/ #include <errno.h> +#include <float.h> #include "endian.h" #include <dla.h> #include "mpa.h" @@ -91,6 +92,11 @@ tan (double x) /* (I) The case abs(x) <= 1.259e-8 */ if (w <= g1.d) { + if (w < DBL_MIN) + { + double force_underflow = x * x; + math_force_eval (force_underflow); + } retval = x; goto ret; } |