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Bruce Evans 12be4e0d5a Fixed 2 bugs in the computation /* t_h=ax+bp[k] High */.
(1) The bit for the 1.0 part of bp[k] was right shifted by 4.  This seems
    to have been caused by a typo in converting e_pow.c to e_powf.c.
(2) The lower 12 bits of ax+bp[k] were not discarded, so t_h was actually
    plain ax+bp[k].  This seems to have been caused by a logic error in
    the conversion.

These bugs gave wrong results like:

    powf(-1.1, 101.0) = -15158.703 (should be -15158.707)
      hex values: BF8CCCCD 42CA0000 C66CDAD0 C66CDAD4

Fixing (1) gives a result wrong in the opposite direction (hex C66CDAD8),
and fixing (2) gives the correct result.

ucbtest has been reporting this particular wrong result on i386 systems
with unpatched libraries for 9 years.  I finally figured out the extent
of the bugs.  On i386's they are normally hidden by extra precision.
We use the trick of representing floats as a sum of 2 floats (one much
smaller) to get extra precision in intermediate calculations without
explicitly using more than float precision.  This trick is just a
pessimization when extra precision is available naturally (as it always
is when dealing with IEEE single precision, so the float precision part
of the library is mostly misimplemented).  (1) and (2) break the trick
in different ways, except on i386's it turns out that the intermediate
calculations are done in enough precision to mask both the bugs and
the limited precision of the float variables (as far as ucbtest can
check).

ucbtest detects the bugs because it forces float precision, but this
is not a normal mode of operation so the bug normally has little effect
on i386's.

On systems that do float arithmetic in float precision, e.g., amd64's,
there is no accidental extra precision and the bugs just give wrong
results.
2004-06-01 18:08:39 +00:00
bin Fix so `ps' catches and complains about null-values specified for a 2004-06-01 03:01:51 +00:00
contrib FreeBSD-ify the manpage. Our inetd does not support bind-address:port syntax 2004-05-27 23:51:05 +00:00
crypto Regenerate. 2004-04-20 09:49:37 +00:00
etc Add common share/locale directories (everything used by >= 5 ports [1]) and 2004-05-31 07:34:40 +00:00
games Consistently credit President Truman as Harry S. Truman. 2004-06-01 09:45:16 +00:00
gnu Remove componenst which are not part of GCC 3.3 and which are not likely 2004-05-29 04:05:37 +00:00
include Use __isctype() instead of __istype() for iswdigit() and iswxdigit() for 2004-05-31 12:44:50 +00:00
kerberos5 Update version strings for Heimdal: 0.6 -> 0.6.1 2004-04-13 16:41:00 +00:00
lib Fixed 2 bugs in the computation /* t_h=ax+bp[k] High */. 2004-06-01 18:08:39 +00:00
libexec give out a little more information in case of a missing dependency 2004-05-28 00:05:28 +00:00
release MFC: cron(8) -j and -J options. 2004-05-31 17:27:01 +00:00
rescue Remove dangling raidctl reference 2004-03-16 13:42:23 +00:00
sbin Fix typo. 2004-05-30 17:40:39 +00:00
secure Import the openssl conf for arm. 2004-05-14 12:26:51 +00:00
share Describe pkg_version_index 2004-05-30 20:32:00 +00:00
sys Add GIANT_REQUIRED to kqueue_close(), since kqueue currently requires 2004-06-01 18:05:41 +00:00
tools Add trailing backslash missing from previous checkin. 2004-05-28 21:26:49 +00:00
usr.bin Add Alice Liddell, Christopher Robin Milne and Winnie-the-Pooh, who 2004-06-01 09:43:22 +00:00
usr.sbin Fixed manpage's synopsis, and synchronized it with the program's usage(). 2004-06-01 09:34:04 +00:00
COPYRIGHT
installworld_newk
installworld_oldk
MAINTAINERS Add myself as maintainer for geom_nop, geom_stripe and geom(8). 2004-05-20 12:44:23 +00:00
Makefile Add a kernel-toolchain target which only builds the bits required to build 2004-04-13 13:42:01 +00:00
Makefile.inc1 Allow buildworld and friends to complete when make(1) is called 2004-05-17 16:19:51 +00:00
README
UPDATING Recompile of ipfw(8) is required because of new ipfw option (versrcreach). 2004-04-23 14:33:30 +00:00
UPDATING.64BTT Add a tip for people who are using database-related ports on a sparc64 2004-03-17 01:59:47 +00:00

This is the top level of the FreeBSD source directory.  This file
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For copyright information, please see the file COPYRIGHT in this
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Building a kernel is a somewhat more involved process, documentation
for which can be found at:
   http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig.html
And in the config(8) man page.
Note: If you want to build and install the kernel with the
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The sample kernel configuration files reside in the sys/<arch>/conf
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Source Roadmap:
---------------
bin		System/user commands.

contrib		Packages contributed by 3rd parties.

crypto		Cryptography stuff (see crypto/README).

etc		Template files for /etc.

games		Amusements.

gnu		Various commands and libraries under the GNU Public License.
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include		System include files.

kerberos5	Kerberos5 (Heimdal) package.

lib		System libraries.

libexec		System daemons.

release		Release building Makefile & associated tools.

sbin		System commands.

secure		Cryptographic libraries and commands.

share		Shared resources.

sys		Kernel sources.

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usr.sbin	System administration commands.


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