some cleanup; tested by sthen@ on a ports build

relevant. from Mark Karpilovskij.
ok millert

cleanups.  From Jan Kokemueller.  OK deraadt@

(w/ _dlctl reference) into static executables.  It's all Mark's code so
put his preferred copyright on it.
ok kettenis@

to control which symbols are exported from the shared library.
ok guenther@, deraadt@, jca@

_libc___cxa_thread_atexit_impl reference on gcc architectures that breaks
the build.

interface is also made available as __cxa_thread_atexit_impl to satisfy the
needs of GNU libstdc++.
ok guenther@, millert@

to builtins like mem{set,cpy,move} and __stack_smash_handler.  So, when
building with clang, instead mark those as protected visibility to get rid
of the PLT relocations.  We can't take the address of them then, but that's
ok: it's a build-time error not a run-time error.
ok kettenis@

with "warning: " since 2003, so the messages themselves need not
contain the prefix anymore.
From Scott Cheloha
ok jca, deraadt

but not all.  From Peter J. Philipp.

which results in an internal double free when internal functions are not
in use.
ok otto@

OK deraadt@ jca@ jmc@

ok tb@ tedu@

Complete in the sense that all POSIX *locale(3) and *_l(3) functions
are included, but in OpenBSD, we of course only really care about
LC_CTYPE and we only support ASCII and UTF-8.
With important help from kettenis@, guenther@, and jca@.
Repeated testing in ports bulk builds by naddy@.
Additional testing by jca@, sebastia@, dcoppa@, and others.
OK kettenis@ dcoppa@, and guenther@ on an earlier version.
Riding guenther@'s libc/librthread major bump.

POSIX 2001 instead of POSIX.1c suggested by millert@ and jmc@, ok jmc@

messages, to avoid pulling in piles of other machinery unnecessarily
problem observed by schwarze@
ok deraadt@ millert@

ok tedu@

found with regress/usr.bin/mandoc/db/dbm_dump;
OK jmc@

definite value in the size == 0 case

is not initialized. Problem spotted by Carlin Bingham; ok phessler@ tedu@

prefix if the character following it is a valid hex char.  The C99
standard is clear that given the string "0xy" zero should be returned
and endptr set to point to the "x".  OK deraadt@ espie@

From Klemens Nanni

src/lib/libc/gen/tree.c is a copy of src/sys/kern/subr_tree.c, but with
annotations for symbol visibility. changes to one should be reflected
in the other.
the malloc debug code that uses RB code is ported to RBT.
because libc provides the RBT code, procmap doesn't have to reach into
the kernel and build subr_tree.c itself now.
mild enthusiasm from many
ok guenther@

insertion sort (when the number of elements is < 7).

Previously they would be swapped a byte at a time when sizeof(int)
!= sizeof(long).  Idea from FreeBSD.

exceeds 2 lg N and add a reference to the introsort paper.

when the recursion depth reaches 2*lg(n + 1).  This avoids quicksort's
quadratic behavior for pathological input without appreciably
changing the average run time.

side of the array being partitioned to save on stack space.  Greater
savings can be gained by choosing recursion for the smaller side
of the partition and eliminating recursion for the larger side.
This also results in a small but measurable performance gain.
OK otto@ schwarze@

From "fenderq" on freenode via tj@

- document posix_memalign() does not play nice with reacallocarray(3) and
freezero(3)

use fallback mechanims if unsuccessful.
The design of Linux getrandom is broken.  It has an
uninitialized phase coupled with blocking behaviour, which
is unacceptable from within a library at boot time without
possible recovery.
ok deraadt@ jsing@

size if canaries are enabled. In that case we have the exact requested
size of the allocation.  But we can at least check the given size
against the chunk size if C is not enabled. Plus add some braces
so my brain doesn't have to scan for dangling else problems when I
see this code.

to separate the open(/dev/ptm) from the ioctl(PTMGET) for privilege
separation or pledge().
Based on a diff from reyk@.
ok deraadt millert