UMTX_OP_WAIT. Upper 16bits is enough to hold a clock id, and lower
16bits is used to pass flags. The change saves a clock_gettime() syscall
from libthr.
Advantages:
- Reduces the number of different license versions in the tree
- Eliminates a typo
- Removes some incorrect author attributions due to c/p
- Removes c/p error potential for future pmc manpages
Approved by: jkoshy, gnn, rpaulo, fabient (copyright holders)
MFC after: 1 week
initialize the cache of the system information as it was done for the
dynamic libc. This removes several sysctls from the static binary
startup.
Use the aux vector to fill the single struct dl_phdr_info describing
the static binary itself, to implement dl_iterate_phdr(3) for the
static binaries. [1]
Based on the submission by: John Marino <draco marino st> [1]
Tested by: flo (sparc64)
MFC after: 2 weeks
- Address performance regressions encountered by das@ by caching per-thread
data in TLS where available.
- Add a __NO_TLS flag to cdefs.h to indicate where not available.
- Reorganise the xlocale.h definitions into xlocale/*.h so that they can be
included from multiple places.
- Export the POSIX2008 subset of xlocale when POSIX2008 says it should be
exported, independently of whether xlocale.h is included.
- Fix the bug where programs using ctype functions always assumed ASCII unless
recompiled.
- Fix some style(9) violations.
Reviewed by: brooks (mentor)
Approved by: dim (mentor)
The reasoning behind this, is that if we are consistent in our
documentation about the uint*_t stuff, people will be less tempted to
write new code that uses the non-standard types.
I am not going to bump the man page dates, as these changes can be
considered style nits. The meaning of the man pages is unaffected.
MFC after: 1 month
Ignore the NAT_T extension types so we can at least dump the SADB from
the in-base libipsec/setkey without error when NAT_T support is present
in the kernel, though not printing the additional information yet.
However in case there is no NAT_T support in kernel still consider them
to be an error.
MFC after: 8 weeks
At first, I added a utility called utxrm(8) to remove stale entries from
the user accounting database. It seems there are cases in which we need
to perform different operations on the database as well. Simply rename
utxrm(8) to utx(8) and place the old code under the "rm" command.
In addition to "rm", this tool supports "boot" and "shutdown", which are
going to be used by an rc-script which I am going to commit separately.
If the utmpx database gets updated while an application is reading it,
there is a chance the reading application processes partially
overwritten entries. To solve this, make sure we always read a multiple
of sizeof(struct futx) at a time.
MFC after: 2 weeks
conditional code parts not used by or applicable to FreeBSD.
The new implementation is supposed to be able to cope with changes to
the 'l' versions of the msghdr structs now used as well as to if_data
allowing future changes without breaking things.
This restores carp(4) config support in HEAD after r231504.
Reviewed by: glebius, brooks
MFC After: 3 months
on extended and extensible structs if_msghdrl and ifa_msghdrl. This
will allow us to extend both the msghdrl structs and eventually if_data
in the future without breaking the ABI.
Bump __FreeBSD_version to allow ports to more easily detect the new API.
Reviewed by: glebius, brooks
MFC after: 3 days
LOGIN_SETPRIORITY is set, and setting the priority (rtprio or
setpriority) fails.
PR: kern/164238
Submitted by: Alexander Wittig <alexander@wittig.name>
Reviewed by: des
Approved by: cperciva
MFC after: 1 month
when the child process execs daemon's target program thanks to flock(2)
semantics. So, we apparently have to leak the open pidfile's file
descriptor to keep the lock for the pidfile(3) functions to work properly.
Test case demonstrated by trociny:
ref8-amd64:/home/trociny% uname -r
8.2-STABLE
ref8-amd64:/home/trociny% daemon -p /tmp/sleep.pid sleep 10
ref8-amd64:/home/trociny% daemon -p /tmp/sleep.pid sleep 10
daemon: process already running, pid: 19799
kopusha:~% uname -r
10.0-CURRENT
kopusha:~% daemon -p /tmp/sleep.pid sleep 10
kopusha:~% daemon -p /tmp/sleep.pid sleep 10
kopusha:~%
checking the returned oldlen: when ENOMEM is due to the supplied
buffer being too short the return oldlen is equal to buffer size.
Without this additional check kvm_getprocs() gets stuck in loop if the
returned ENOMEM was due the exceeded memorylocked limit. This is
easily can be observed running `limits -l 1k top'.
Submitted by: Andrey Zonov <andrey zonov org>
MFC after: 1 week
the signal handlers with the context information in the deferrred
case.
Only enable the use of getcontextx(3) in the deferred signal delivery
code on amd64 and i386. Sparc64 seems to have some undetermined issues
with interaction of alloca(3) and signal delivery.
Tested by: flo (who also provided sparc64 harware access for me), pho
Discussed with: marius
MFC after: 1 month
fit into existing mcontext_t.
On i386 and amd64 do return the extended FPU states using
getcontextx(3). For other architectures, getcontextx(3) returns the
same information as getcontext(2).
Tested by: pho
MFC after: 1 month
profiling and kernel profiling. To enable kernel profiling one has to build
kgmon(8). I will enable the build once I managed to build and test powerpc
(32-bit) kernels with profiling support.
- add a powerpc64 PROF_PROLOGUE for _mcount.
- add macros to avoid adding the PROF_PROLOGUE in certain assembly entries.
- apply these macros where needed.
- add size information to the MCOUNT function.
MFC after: 3 weeks, together with r230291
NetBSD's rev 1.6 of this file, on !defined(SOFTFLOAT_FOR_GCC). These
functions are provided by libgcc, so we don't need them. This should
unbreak mips.
the function bodies require only 2 to 10 instructions. However, it
leads to application binaries that refer to a private ABI, namely, the
softfloat innards in libc. This could complicate future changes in
the implementation of the floating-point emulation layer, so it seems
best to have programs refer to the official fe* entry points in libm.
original vendor, but we're using their heavily modified version.)
This brings in functions for long double emulation (both extended and
quad formats), which may be useful for testing, and also for replacing
libc/sparc64/fpu/.
the LDADD/DPADD to lose the -lpam, and causing openpam_dynamic() to fail
due to "openpam_get_options" being undefined.
This would cause obscure console log messages like:
openpam_dynamic(): No error: 0
openpam_load_module(): no pam_unix.so found
and other helpful messages which are no help in diagnosing the problem.
Fortunately this change was not mfc'ed to 9.x, it isn't broken there.
progress information. The first is that fetch_read() (used in the HTTP
code but not the FTP code) can enter an infinite loop if it has previously
been interrupted by a signal. The second is that when it is interrupted,
fetch_read() will discard any data it may have read up to that point.
Luckily, both bugs are extremely timing-sensitive and therefore difficult
to trigger.
PR: bin/153240
Submitted by: Mark <markjdb@gmail.com>
MFC after: 3 weeks
use softfloat.
Thanks to Ian Lepore for testing and debugging this patch. The fenv
regression tests pass (at least for Ian's arm chip) with this change.
dynamic rounding modes, but FPUless chips that use softfloat can support it
because everything is emulated anyway. (We presently have incomplete
support for hardware FPUs.)
Submitted by: Ian Lepore
requested value was handled incorrectly, and the function retuned NULL
instead of the truncated result.
Fix this and also remove unnecessary check for buf != NULL, which alway
retuns true.
MFC after: 3 days
The wtmpcvt(1) utility converts wtmp files to the new format used by
utmpx(3). Now that HEAD has been branched to stable/9 and 9.0 is
released, there is no need for it in HEAD.
MFC after: never
for pidfh in libutil.h in its place.
This allows us to hide the contents of the pidfh structure, and also
allowed removal of the "#ifdef _SYS_PARAM_H" guard from around the
pidfile_* function prototypes.
Suggested by pjd.
The C11 folks reinvented the wheel by introducing an aligned version of
malloc(3) called aligned_alloc(3), instead of posix_memalign(3). Instead
of returning the allocation by reference, it returns the address, just
like malloc(3).
Reviewed by: jasone@
This switches us to using -isoC-2011 as the symbol name which is used by
groff and mdocml. It follows the change to 4 digit years as done with
IEEE Std 1003 post-1999.
MFC after: 2 weeks (groff changes only)
This allows people to still write statically linked applications that
call strchr() or strrchr() and have a local variable or function called
index.
Discussed with: bde@
http://www.graphicsgems.org/
At the time it claimed to be 3-4 times faster than the traditional
algorithm.
PR: 18769
Approved by: jhb (mentor)
MFC after: 2 weeks
The index() and rindex() functions were marked LEGACY in the 2001
revision of POSIX and were subsequently removed from the 2008 revision.
The strchr() and strrchr() functions are part of the C standard.
This makes the source code a lot more consistent, as most of these C
files also call into other str*() routines. In fact, about a dozen
already perform strchr() calls.
As I looked through the C library, I noticed the FreeBSD MIPS port has a
hand-written version of index(). This is nice, if it weren't for the
fact that most applications call strchr() instead.
Also, on the other architectures index() and strchr() are identical,
meaning we have two identical pieces of code in the C library and
statically linked applications.
Solve this by naming the actual file strchr.[cS] and let it use
__strong_reference()/STRONG_ALIAS() to provide the index() routine. Do
the same for rindex()/strrchr().
This seems to make the C libraries and static binaries slightly smaller,
but this reduction in size seems negligible.
problem by adding -fno-strict-aliasing to CFLAGS. Since this is a global
issue that just happened to manifest on PowerPC, add this to CFLAGS
unconditionally.
MFC after: 1 week
This version of libcompiler_rt adds support for __mulo[sdt]i4(), which
computes a multiply and its overflow flag. There are also a lot of
cleanup fixes to headers that don't really affect us.
Updating to this revision should make it a bit easier to contribute
changes back to the LLVM developers.
lib/libc/gen/strtofflags.c became const, but gcc did not warn about
assigning its members to non-const pointers. Clang warned about this
with:
lib/libc/gen/strtofflags.c:98:12: error: assigning to 'char *' from 'const char *' discards qualifiers [-Werror,-Wincompatible-pointer-types]
for (sp = mapping[i].invert ? mapping[i].name :
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Reviewed by: jilles
The built-in atomic operations are not implemented in our version of GCC
4.2 for the ARM and MIPS architectures. Instead of emitting locked
instructions, they generate calls to functions that can be implemented
in the C runtime.
Only implement the atomic operations that are used by <stdatomic.h> for
datatype sizes that are supported by atomic(9). This means that on these
architectures, we can only use atomic operations on 32-bits and 64-bits
variables, which is typically sufficient.
This makes <stdatomic.h> work on all architectures except MIPS, since
MIPS and SPARC64 still use libgcc. Converting these architectures to
libcompiler_rt is on my todo list.
This library implements the C11 threads interface on top of the pthreads
library. As discussed on the lists, the preferred way to implement
this, is as a separate library.
It is unlikely that these functions will be used a lot in the future. It
would have been easier if the C11 working group standardized (a subset
of) pthreads and clock_nanosleep(). Having it as a separate library
allows the embedded people to omit it from their system.
Discussed on: arch@, threads@
Add an API for alerting internal libc routines to the presence of
"unsafe" paths post-chroot, and use it in ftpd. [11:07]
Fix a buffer overflow in telnetd. [11:08]
Make pam_ssh ignore unpassphrased keys unless the "nullok" option is
specified. [11:09]
Add sanity checking of service names in pam_start. [11:10]
Approved by: so (cperciva)
Approved by: re (bz)
Security: FreeBSD-SA-11:06.bind
Security: FreeBSD-SA-11:07.chroot
Security: FreeBSD-SA-11:08.telnetd
Security: FreeBSD-SA-11:09.pam_ssh
Security: FreeBSD-SA-11:10.pam
At work we have a single tftp server that provides installation data for
a variety of operating systems. I'd rather place our FreeBSD-related
files in a subdirectory, instead of the root.
It would be nice if this setting could be run-time configurable, but at
least in our specific case, this is not possible, as pxeboot is
chainloaded through pxelinux.
Sponsored by: Kumina bv
3730:
Fix issue 174 (Windows path names, not relevant for FreeBSD)
3734:
Merge r1989: archive_clear_error should set errno to 0.
3735:
Merge r3247 from trunk: Clear errors before returning
from archive_read_support_format_all()
3799:
Check the position before dereferencing the pointer.
This avoids dereferencing one byte past the end of a string
3824:
Merge r3823 from trunk for issue 199 (hang in iso9660 reading)
Obtained from: http://code.google.com/p/libarchive
MFC after: 2 weeks
The following additional vendor revisions are applied:
Revision 3740:
Use archive_clear_error() to clear the error markers.
Obtained from: http://code.google.com/p/libarchive
MFC after: 2 weeks
Fixes extraction of Zip entries that use length-at-end without specifying
either the compressed or uncompressed length. In particular, fixes bsdtar
extraction of such files.
Obtained from: http://code.google.com/p/libarchive
Reported by: Patrick Lamaiziere <patfbsd@davenulle.org> (freebsd-stable@)
MFC after: 1 week
from scratch, copying needed functionality from the old implemenation
on demand, with a thorough review of all code. The main change is that
interface layer has been removed from the CARP. Now redundant addresses
are configured exactly on the interfaces, they run on.
The CARP configuration itself is, as before, configured and read via
SIOCSVH/SIOCGVH ioctls. A new prefix created with SIOCAIFADDR or
SIOCAIFADDR_IN6 may now be configured to a particular virtual host id,
which makes the prefix redundant.
ifconfig(8) semantics has been changed too: now one doesn't need
to clone carpXX interface, he/she should directly configure a vhid
on a Ethernet interface.
To supply vhid data from the kernel to an application the getifaddrs(8)
function had been changed to pass ifam_data with each address. [1]
The new implementation definitely closes all PRs related to carp(4)
being an interface, and may close several others. It also allows
to run a single redundant IP per interface.
Big thanks to Bjoern Zeeb for his help with inet6 part of patch, for
idea on using ifam_data and for several rounds of reviewing!
PR: kern/117000, kern/126945, kern/126714, kern/120130, kern/117448
Reviewed by: bz
Submitted by: bz [1]
- if pw is NULL and oldpw is not NULL then the oldpw is deleted
- if pw->pw_name != oldpw->pw_name but pw->pw_uid == oldpw->pw_uid
then it renames the user
add new gr_* functions so now gr_util API is similar to pw_util API,
this allow to manipulate groups in a safe way.
Reviewed by: des
Approved by: des
MFC after: 1 month
yet (see LLVM PR 9788), and warns about it, rub it out for now. When
clang grows support for this attribute, I will revert this again.
MFC after: 1 week
conversion between enum desdir/desmode from include/rpc/des.h, and enum
desdir/desmode from include/rpcsvc/crypt.x. These are actually
different enums, with different value names, but by accident the integer
representation of the enum values happened to be the same.
MFC after: 1 week
warn about it. I guess this was originally done to silence a bogus
warning by an older version of gcc, but I could not reproduce it with
any version of gcc that I have access to.
MFC after: 1 week
versions of pthread_md.h have a special case of dereferencing a null
pointer. Clang warns about this with:
In file included from lib/libthr/arch/i386/i386/pthread_md.c:36:
lib/libthr/arch/i386/include/pthread_md.h:96:10: error: indirection of non-volatile null pointer will be deleted, not trap [-Werror,-Wnull-dereference]
return (TCB_GET32(tcb_self));
^~~~~~~~~~~~~~~~~~~
lib/libthr/arch/i386/include/pthread_md.h:73:13: note: expanded from:
: "m" (*(u_int *)(__tcb_offset(name)))); \
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
lib/libthr/arch/i386/include/pthread_md.h:96:10: note: consider using __builtin_trap() or qualifying pointer with 'volatile'
Since this indirection is done relative to the fs or gs segment, to
retrieve thread-specific data, it is an exception to the rule.
Therefore, add a volatile qualifier to tell the compiler we really want
to dereference a zero address.
MFC after: 1 week
__noreturn macro and modify the other exiting functions to use it.
The __noreturn macro, unlike __dead2, must be used BEFORE the function.
This is in line with the C and C++ specifications that place _Noreturn (c1x)
and [[noreturn]] (C++11) in front of the functions. As with __dead2, this
macro falls back to using the GCC attribute.
Unfortunately, clang currently sets the same value for the C version macro
in C99 and C1x modes, so these functions are hidden by default. At some
point before 10.0, I need to go through the headers and clean up the C1x /
C++11 visibility.
Reviewed by: brooks (mentor)
vs. the comment documented "If we are working with a privileged socket,
then take only one attempt". Make the code match.
Furthermore, critical privileged applications that [over] log a vast amount
can look like a DoS to this code. Given it's unlikely the single reattempted
send() will succeeded, avoid usurping the scheduler in a library API for a
single non-critical facility in critical applications.
Obtained from: Juniper Networks
Discussed with: glebius
than silently failing and returning success.
Without this, code calls pthread_once(), receives a return value of
success, and thinks that the passed function has been called.
Approved by: dim (mentor)
not disabled in the usual way (by adding it to __DEFAULT_NO_OPTIONS in
share/mk/bsd.own.mk), and because the test for MK_LIBCPLUSPLUS in
Makefile.inc1 was incorrect.
Pointy hat to: dim
MK_LIBCPLUSPLUS=yes to enable). This is a work-in-progress. It works for
me, but is not guaranteed to work for anyone else and may eat your dog.
To build C++ using libc++, add -stdlib=libc++ to your CXX and LD flags.
Bug reports welcome, bug fixes even more welcome...
Approved by: dim (mentor)
system calls to provide feed-forward clock management capabilities to
userspace processes. ffclock_getcounter() returns the current value of the
kernel's feed-forward clock counter. ffclock_getestimate() returns the current
feed-forward clock parameter estimates and ffclock_setestimate() updates the
feed-forward clock parameter estimates.
- Document the syscalls in the ffclock.2 man page.
- Regenerate the script-derived syscall related files.
Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.
For more information, see http://www.synclab.org/radclock/
Submitted by: Julien Ridoux (jridoux at unimelb edu au)
is unencrypted. This defeats the nullok check, because it means a
non-null passphrase will successfully unlock the key.
To address this, try at first to load the key without a passphrase.
If this succeeds and the user provided a non-empty passphrase *or*
nullok is false, reject the key.
MFC after: 1 week
Noticed by: Guy Helmer <guy.helmer@palisadesystems.com>
load of _l suffixed versions of various standard library functions that use
the global locale, making them take an explicit locale parameter. Also
adds support for per-thread locales. This work was funded by the FreeBSD
Foundation.
Please test any code you have that uses the C standard locale functions!
Reviewed by: das (gdtoa changes)
Approved by: dim (mentor)
allow the built-in operations to be redefined, at least not without
excessive force).
Instead, just disable LLVM's support for atomic operations for now.
Nothing in either clang or the tablegen tools currently depends on it.
This still allows users of head built before r198344 to upgrade to
top-of-head seamlessly.
change here is to ensure that when a process forks after arc4random
is seeded, the parent and child don't observe the same random sequence.
OpenBSD's fix introduces some additional overhead in the form of a
getpid() call. This could be improved upon, e.g., by setting a flag
in fork(), if it proves to be a problem.
This was discussed with secteam (simon, csjp, rwatson) in 2008, shortly
prior to my going out of town and forgetting all about it. The conclusion
was that the problem with forks is worrisome, but it doesn't appear to
have introduced an actual vulnerability for any known programs.
The only significant remaining difference between our arc4random and
OpenBSD's is in how we seed the generator in arc4_stir().
OpenBSD's version (r1.22). While some of our style changes were
indeed small improvements, being able to easily track functionality
changes in OpenBSD seems more useful.
Also fix style bugs in the FreeBSD-specific parts of this file.
No functional changes, as verified with md5.
Some header file parts of this patch were taken from a patch submitted
by Maya Erez <merez@codeaurora.org> to the LibUSB developers list.
MFC after: 1 week
Some consumers of PAM remove the /dev/ component (i.e. login), while
others don't (i.e. su). We must ensure that the /dev/ component is
removed to ensure that the utmpx entries properly work with tools such
as w(1).
Discussed with: des
MFC after: 1 week
to be gcc's default before r198344, calls to atomic builtins will not be
expanded inline. Instead, they will be generated as calls to external
functions (e.g. __sync_fetch_and_add_N), leading to linking errors later
on.
Put in a seatbelt that disables use of atomic builtins in libstdc++ and
llvm, when tuning specifically for the real i386 CPU. This does not
protect against all possible issues, but it is better than nothing.
This variable was added in r82352 back in 2001, but even then it didn't
have any use. Because it's not marked static, the C compiler won't
complain about it.
Discussed with: des
The size passed to strlcat() must depend on the input length, not the
output length. Because the input and output buffers are equal in size,
the resulting binary does not change at all.
madvise(2) except that it operates on a file descriptor instead of a
memory region. It is currently only supported on regular files.
Just as with madvise(2), the advice given to posix_fadvise(2) can be
divided into two types. The first type provide hints about data access
patterns and are used in the file read and write routines to modify the
I/O flags passed down to VOP_READ() and VOP_WRITE(). These modes are
thus filesystem independent. Note that to ease implementation (and
since this API is only advisory anyway), only a single non-normal
range is allowed per file descriptor.
The second type of hints are used to hint to the OS that data will or
will not be used. These hints are implemented via a new VOP_ADVISE().
A default implementation is provided which does nothing for the WILLNEED
request and attempts to move any clean pages to the cache page queue for
the DONTNEED request. This latter case required two other changes.
First, a new V_CLEANONLY flag was added to vinvalbuf(). This requests
vinvalbuf() to only flush clean buffers for the vnode from the buffer
cache and to not remove any backing pages from the vnode. This is
used to ensure clean pages are not wired into the buffer cache before
attempting to move them to the cache page queue. The second change adds
a new vm_object_page_cache() method. This method is somewhat similar to
vm_object_page_remove() except that instead of freeing each page in the
specified range, it attempts to move clean pages to the cache queue if
possible.
To preserve the ABI of struct file, the f_cdevpriv pointer is now reused
in a union to point to the currently active advice region if one is
present for regular files.
Reviewed by: jilles, kib, arch@
Approved by: re (kib)
MFC after: 1 month
the word alignment, some versions of gcc do require 16-byte alignment.
Make sure the stack is 16-byte aligned before calling a subroutine.
Inspired by: PR amd64/162214
MFC after: 1 week
as it is required by amd64 ABI. Add a comment for the places were
the stack is accidentally properly aligned already.
PR: amd64/162214
Submitted by: yamayan <yamayan kbh biglobe ne jp>
MFC after: 1 week
When booting the system, truncate the utx.active file, but do write the
BOOT_TIME record into it afterwards. This allows one to obtain the boot
time of the system as follows:
struct utmpx u1 = { .ut_type = BOOT_TIME }, *u2;
setutxent();
u2 = getutxid(&u1);
Now, the boot time is stored in u2->ut_tv, just like on Linux and other
systems.
We don't open the utx.active file with O_EXLOCK. It's rather unlikely
that other applications use this database at the same time and I want to
prevent the possibility of deadlocks in init(8).
Discussed with: pluknet
working MI one. The MI one only needs to be overridden on machines
with non-IEEE754 arithmetic. (The last supported one was the VAX.)
It can also be overridden if someone comes up with a faster one that
actually passes the regression tests -- but this is harder than it sounds.
- Handle cases where exp(x) would overflow, but ccosh(x) ~= exp(x) / 2
shouldn't.
- Use the ccosh(x) ~= exp(x) / 2 approximation to simplify the calculation
when x is large.
Similarly for csinh(). Also fixed the return value of csinh(-Inf +- 0i).
exp(x) scaled down by some factor, and the challenge is doing this
accurately when exp(x) would overflow. This change replaces all of
the tricks we've been using with common __ldexp_exp() and
__ldexp_cexp() routines that handle all the scaling.
bde plans to improve on this further by moving the guts of exp() into
k_exp.c and handling the scaling in a more direct manner. But the
current approach is simple and adequate for now.
As the underlying block is 4KB if the PMC throughput is low the measurement
will be reported on the next tick. pmcstat(8) use the modified flush API to
reclaim current buffer before displaying next top.
MFC after: 1 month
library," since complex.h, tgmath.h, and fenv.h are also part of the
math library. Replace the outdated sentence with some references to
the other parts.
and the caller requested other process' PID by passing non-NULL pidptr
argument, we will wait at most 100ms for the PID to show up in the file and if
it won't, we will store -1 in *pidptr.
From now on, pidfile_open() function never sets errno to EAGAIN on failure.
In collaboration with: des
MFC after: 1 week
- Rename __kernel_log() to k_log1p().
- Move some of the work that was previously done in the kernel log into
the callers. This enables further refactoring to improve accuracy or
speed, although I don't recall the details.
- Use extra precision when adding the final scaling term, which improves
accuracy.
- Describe and work around compiler problems that break some of the
multiprecision calculations.
A fix for a small bug is also included:
- Add a special case for log*(1). This is needed to ensure that log*(1) == +0
instead of -0, even when the rounding mode is FE_DOWNWARD.
Submitted by: bde
