On BSD-family systems, header <sys/sockio.h> defines socket ioctl
numbers like SIOCGIFCONF. Only AIX is using those now, but it defines
them in <net/if.h> anyway.
Supposing some PostgreSQL hacker wants to test that AIX-only code path
on a more common development system by pretending not to have
getifaddrs(). It's enough to include <sys/ioctl.h>, at least on macOS,
FreeBSD and Linux, and we're already doing that.
SUSv3, all targeted Unixes and modern Windows have getaddrinfo() and
related interfaces. Drop the replacement implementation, and adjust
some headers slightly to make sure that the APIs are visible everywhere
using standard POSIX headers and names.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CA%2BhUKG%2BL_3brvh%3D8e0BW_VfX9h7MtwgN%3DnFHP5o7X2oZucY9dg%40mail.gmail.com
Assume that we can use LWARX hint flags and the LWSYNC instruction
on any PPC machine. The check on the assembler's behavior was only
needed for Apple's old assembler, which is no longer of interest
now that we've de-supported all PPC-era versions of macOS (thanks
to them not having clock_gettime()). Also, given an up-to-date
assembler these instructions work even on Apple's old hardware.
It seems quite unlikely that anyone would be interested in running
current Postgres on PPC hardware that's so old as to not have
these instructions.
Hence, rip out associated configure test and manual configuration
options, and just use the modernized instructions all the time.
Also, update atomics/arch-ppc.h to use these instructions as well.
(It was already using LWSYNC unconditionally in another place,
providing further proof that nobody is using PG on hardware old
enough to have a problem with that.)
Discussion: https://postgr.es/m/166622.1660323391@sss.pgh.pa.us
<sys/resource.h> is in SUSv2 and is on all targeted Unix systems. We
have a replacement for getrusage() on Windows, so let's just move its
declarations into src/include/port/win32/sys/resource.h so that we can
use a standard-looking #include. Also remove an obsolete reference to
CLK_TCK. Also rename src/port/getrusage.c to win32getrusage.c,
following the convention for Windows-only fallback code.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CA%2BhUKG%2BL_3brvh%3D8e0BW_VfX9h7MtwgN%3DnFHP5o7X2oZucY9dg%40mail.gmail.com
<sys/un.h> is in SUSv3 and every targeted Unix has it. Some Windows
tool chains may still lack the approximately equivalent header
<afunix.h>, so we already defined struct sockaddr_un ourselves on that
OS for now. To harmonize things a bit, move our definition into a new
header src/include/port/win32/sys/un.h.
HAVE_UNIX_SOCKETS is now defined unconditionally. We migh remove that
in a separate commit, pending discussion.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA%2BhUKG%2BL_3brvh%3D8e0BW_VfX9h7MtwgN%3DnFHP5o7X2oZucY9dg%40mail.gmail.com
<sys/uio.h> is in SUSv2, and all targeted Unix system have it, so we
might as well drop the probe (in fact we never really needed this one).
It's where struct iovec is defined, and as a common extension, it's also
where non-standard preadv() and pwritev() are declared on systems that
have them.
We should also be able to assume that IOV_MAX is defined on Unix.
To spell out what our pg_iovec.h header does for the OSes in the build
farm as of today:
Windows: our own struct and functions
Solaris, Cygwin: <sys/uio.h>'s struct, our own functions
Every other Unix: <sys/uio.h>'s struct and functions
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CA%2BhUKG%2BL_3brvh%3D8e0BW_VfX9h7MtwgN%3DnFHP5o7X2oZucY9dg%40mail.gmail.com
Previously we fell back to __FUNCTION__ and then NULL. As __func__ is in C99
that shouldn't be necessary anymore.
Solution.pm defined HAVE_FUNCNAME__FUNCTION instead of
HAVE_FUNCNAME__FUNC (originating in 4164e6636e), as at some point in the past
MSVC only supported __FUNCTION__. Our minimum version supports __func__.
Reviewed-By: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/20220807012914.ydz73yte6j3coulo@awork3.anarazel.de
strtof() is in C99 and all targeted systems have it. We can remove the
configure probe and some dead code, but we still need replacement code
for a couple of systems that have known buggy implementations selected
via platform template.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/152683.1659830125%40sss.pgh.pa.us
There's no known supported system needing 1 argument gettimeofday()
support. The test for it was added a long time ago (92c6bf9775). Remove.
Until now we tested whether a gettimeofday() fallback is needed when
targetting windows. Which lead to the odd result that HAVE_GETTIMEOFDAY only
being defined when targetting MinGW (which has gettimeofday() since at least
2007). As the fallback is specific to msvc, remove the configure code and
rename src/port/gettimeofday.c to src/port/win32gettimeofday.c.
While at it, also remove the definition of struct timezone, a forward
declaration of the struct is sufficient.
Reviewed-By: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-By: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/20220806000311.ywx65iuchvj4qn2k@awork3.anarazel.de
strtoll was backfilled with either __strtoll or strtoq on systems without
strtoll. The last such system on the buildfarm was an ancient HP-UX animal. We
don't support HP-UX anymore, so remove.
On other systems strtoll was present, but did not have a declaration. The last
known instance on the buildfarm was running an ancient OSX and shut down in
2019.
Author: Andres Freund <andres@anarazel.de>
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/20220804013546.h65najrzig764jar@awork3.anarazel.de
clock_gettime() is in SUSv2 and all targeted Unix systems have it.
Remove a chunk of fallback code for old Unix is no longer reachable on
modern systems, and untested as of the retirement of build farm animal
prairiedog.
There is no need to retain a HAVE_CLOCK_GETTIME macro here, because it
is already used in a context with Unix and Windows code paths.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA+hUKGJ3LHeP9w5Fgzdr4G8AnEtJ=z=p6hGDEm4qYGEUX5B6fQ@mail.gmail.com
preadv() and pwritev() are not standardized by POSIX, but appeared in
NetBSD in 1999 and were adopted by at least OpenBSD, FreeBSD,
DragonFlyBSD, Linux, AIX, illumos and macOS. We don't use them much
yet, but an active proposal uses them heavily.
In 15, we had two replacement implementations for other OSes: one based
on lseek() + -v function if available for true vector I/O, and the other
based on a loop over p- function.
The former would be an obstacle to hypothetical future multi-threaded
code sharing file descriptors, while the latter would not, since commit
cf112c12. Furthermore, the number of targeted systems that could
benefit from the former's potential upside has dwindled to just one
niche OS, since macOS added the functions and we de-supported HP-UX.
That doesn't seem like a good trade-off.
Therefore, drop the lseek()-based variant, and also the pg_ prefix now
that the file position portability hazard is gone.
At the time of writing, the only systems in our build farm that lack
native preadv/pwritev and thus use fallback code are:
* Solaris (but not illumos)
* macOS before release 11.0
* Windows
With this commit, the above systems will now use the *same* fallback
code, the version that loops over pread()/pwrite(). Windows already
used that (though a later proposal may include true vector I/O for
Windows), so this decision really only affects Solaris, until it gets
around to adding these system calls.
Also remove some useless includes while here.
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA+hUKGJ3LHeP9w5Fgzdr4G8AnEtJ=z=p6hGDEm4qYGEUX5B6fQ@mail.gmail.com
pread() and pwrite() are in SUSv2, and all targeted Unix systems have
them.
Previously, we defined pg_pread and pg_pwrite to emulate these function
with lseek() on old Unixen. The names with a pg_ prefix were a reminder
of a portability hazard: they might change the current file position.
That hazard is gone, so we can drop the prefixes.
Since the remaining replacement code is Windows-only, move it into
src/port/win32p{read,write}.c, and move the declarations into
src/include/port/win32_port.h.
No need for vestigial HAVE_PREAD, HAVE_PWRITE macros as they were only
used for declarations in port.h which have now moved into win32_port.h.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Greg Stark <stark@mit.edu>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA+hUKGJ3LHeP9w5Fgzdr4G8AnEtJ=z=p6hGDEm4qYGEUX5B6fQ@mail.gmail.com
setenv() and unsetenv() are in SUSv3 and targeted Unix systems have
them. We still need special code for these on Windows, but that doesn't
require a configure probe.
This marks the first time we require a SUSv3 (POSIX.1-2001) facility
(rather than SUSv2). The replacement code removed here was not needed
on any targeted system or any known non-EOL'd Unix system, and was
therefore dead and untested.
No need for vestigial HAVE_SETENV and HAVE_UNSETENV macros, because we
provide a replacement for Windows, and we didn't previously test the
macros.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Greg Stark <stark@mit.edu>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA+hUKGJ3LHeP9w5Fgzdr4G8AnEtJ=z=p6hGDEm4qYGEUX5B6fQ@mail.gmail.com
poll() and <poll.h> are in SUSv2 and all targeted Unix systems have
them.
Retain HAVE_POLL and HAVE_POLL_H macros for readability. There's an
error in latch.c that is now unreachable (since we always have one of
WIN32 or HAVE_POLL defined), but that falls out of a decision to keep
using defined(HAVE_POLL) instead of !defined(WIN32) to guard the poll()
code.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA+hUKGJ3LHeP9w5Fgzdr4G8AnEtJ=z=p6hGDEm4qYGEUX5B6fQ@mail.gmail.com
link() is in SUSv2 and all targeted Unix systems have it. We have
replacement code for Windows that doesn't require a configure probe.
Since only Windows needs it, rename src/port/link.c to win32link.c like
other similar things.
There is no need for a vestigial HAVE_LINK macro, because we expect all
Unix and, with our replacement function, Windows systems to have it, so
we didn't have any tests around link() usage.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA+hUKGJ3LHeP9w5Fgzdr4G8AnEtJ=z=p6hGDEm4qYGEUX5B6fQ@mail.gmail.com
symlink() and readlink() are in SUSv2 and all targeted Unix systems have
them. We have partial emulation on Windows. Code that raised runtime
errors on systems without it has been dead for years, so we can remove
that and also references to such systems in the documentation.
Define HAVE_READLINK and HAVE_SYMLINK macros on Unix. Our Windows
replacement functions based on junction points can't be used for
relative paths or for non-directories, so the macros can be used to
check for full symlink support. The places that deal with tablespaces
can just use symlink functions without checking the macros. (If they
did check the macros, they'd need to provide an #else branch with a
runtime or compile time error, and it'd be dead code.)
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA+hUKGJ3LHeP9w5Fgzdr4G8AnEtJ=z=p6hGDEm4qYGEUX5B6fQ@mail.gmail.com
setsid() is in SUSv2 and all targeted Unix systems have it. Retain a
HAVE_SETSID macro, defined on Unix only. That's easier to understand
than !defined(WIN32), for the optional code it governs.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA+hUKGJ3LHeP9w5Fgzdr4G8AnEtJ=z=p6hGDEm4qYGEUX5B6fQ@mail.gmail.com
shm_open() is in SUSv2 and all targeted Unix systems have it.
We retain a HAVE_SHM_OPEN macro, because it's clearer to readers than
something like !defined(WIN32).
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA+hUKGJ3LHeP9w5Fgzdr4G8AnEtJ=z=p6hGDEm4qYGEUX5B6fQ@mail.gmail.com
getrlimit() is in SUSv2 and all targeted systems have it.
Windows doesn't have it. We could just use #ifndef WIN32, but for a
little more explanation about why we're making things conditional, let's
retain the HAVE_GETRLIMIT macro. It's defined in port.h for Unix systems.
On systems that have it, it's not necessary to test for RLIMIT_CORE,
RLIMIT_STACK or RLIMIT_NOFILE macros, since SUSv2 requires those and all
targeted systems have them. Also remove references to a pre-historic
alternative spelling of RLIMIT_NOFILE, and coding that seemed to believe
that Cygwin didn't have it.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA+hUKGJ3LHeP9w5Fgzdr4G8AnEtJ=z=p6hGDEm4qYGEUX5B6fQ@mail.gmail.com
dlopen() is in SUSv2 and all targeted Unix systems have it. We still
need replacement functions for Windows, but we don't need a configure
probe for that.
Since it's no longer needed by other operating systems, rename dlopen.c
to win32dlopen.c and move the declarations into win32_port.h.
Likewise, the macros RTLD_NOW and RTLD_GLOBAL now only need to be
defined on Windows, since all targeted Unix systems have 'em.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA+hUKGJ3LHeP9w5Fgzdr4G8AnEtJ=z=p6hGDEm4qYGEUX5B6fQ@mail.gmail.com
sigwait() is in SUSv2 and all targeted Unix systems have it. An earlier
pre-standard function prototype existed on some older systems, but we
no longer need a workaround for that.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Greg Stark <stark@mit.edu>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/CA+hUKGJ3LHeP9w5Fgzdr4G8AnEtJ=z=p6hGDEm4qYGEUX5B6fQ@mail.gmail.com
getrusage() is in SUSv2 and all targeted Unix systems have it.
Note that POSIX only covers ru_utime and ru_stime and we rely on many
more fields without any kind of configure probe, but that predates this
commit.
The only supported system we need replacement code for now is Windows,
and that can be done without a configure probe.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Greg Stark <stark@mit.edu>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/CA+hUKGJ3LHeP9w5Fgzdr4G8AnEtJ=z=p6hGDEm4qYGEUX5B6fQ@mail.gmail.com
Commit 4f658dc8 provided the traditional BSD fls() function in
src/port/fls.c so it could be used in several places. Later we added a
bunch of similar facilities in pg_bitutils.h, based on compiler
builtins that map to hardware instructions. It's a bit confusing to
have both 1-based and 0-based variants of this operation in use in
different parts of the tree, and neither is blessed by a standard.
Let's drop fls.c and the configure probe, and reuse the newer code.
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CA%2BhUKG%2B7dSX1XF8yFGmYk-%3D48dbjH2kmzZj16XvhbrWP-9BzRg%40mail.gmail.com
Until now postgres built extension libraries with global visibility, i.e.
exporting all symbols. On the one platform where that behavior is not
natively available, namely windows, we emulate it by analyzing the input files
to the shared library and exporting all the symbols therein.
Not exporting all symbols is actually desirable, as it can improve loading
speed, reduces the likelihood of symbol conflicts and can improve intra
extension library function call performance. It also makes the non-windows
builds more similar to windows builds.
Additionally, with meson implementing the export-all-symbols behavior for
windows, turns out to be more verbose than desirable.
This patch adds support for hiding symbols by default and, to counteract that,
explicit symbol visibility annotation for compilers that support
__attribute__((visibility("default"))) and -fvisibility=hidden. That is
expected to be most, if not all, compilers except msvc (for which we already
support explicit symbol export annotations).
Now that extension library symbols are explicitly exported, we don't need to
export all symbols on windows anymore, hence remove that behavior from
src/tools/msvc. The supporting code can't be removed, as we still need to
export all symbols from the main postgres binary.
Author: Andres Freund <andres@anarazel.de>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/20211101020311.av6hphdl6xbjbuif@alap3.anarazel.de
HP-UX hardware is no longer produced, build farm coverage recently
ended, and there are no known active maintainers targeting this OS.
Since there is a major rewrite of the build system in the pipeline for
PostgreSQL 16, and that requires development, testing and maintainance
for each OS and tool chain, it seems like a good time to drop support
for:
* HP-UX, the operating system.
* HP aCC, the HP-UX native compiler.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Discussion: https://postgr.es/m/1415825.1656893299%40sss.pgh.pa.us
The test for lz4.h used AC_CHECK_HEADERS, but nothing was using the
resulting symbol HAVE_LZ4_H. Change this to use AC_CHECK_HEADER
instead. This was probably an oversight, seeing that the nearby
similar tests do this correctly.
The current implementation supports exactly one IP address in a server
certificate's Common Name, which is brittle (the strings must match
exactly). This patch adds support for IPv4 and IPv6 addresses in a
server's Subject Alternative Names.
Per discussion on-list:
- If the client's expected host is an IP address, we allow fallback to
the Subject Common Name if an iPAddress SAN is not present, even if
a dNSName is present. This matches the behavior of NSS, in
violation of the relevant RFCs.
- We also, counter-intuitively, match IP addresses embedded in dNSName
SANs. From inspection this appears to have been the behavior since
the SAN matching feature was introduced in acd08d76.
- Unlike NSS, we don't map IPv4 to IPv6 addresses, or vice-versa.
Author: Jacob Champion <pchampion@vmware.com>
Co-authored-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Co-authored-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://www.postgresql.org/message-id/flat/9f5f20974cd3a4091a788cf7f00ab663d5fcdffe.camel@vmware.com
Move DLSUFFIX from makefiles into header files for all platforms.
Move the DLSUFFIX assignment from src/makefiles/ to src/templates/,
have configure read it, and then substitute it into Makefile.global
and pg_config.h. This avoids the need for all makefile rules that
need it to locally set CPPFLAGS. It also resolves an inconsistent
setup between the two Windows build systems.
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/2f9861fb-8969-9005-7518-b8e60f2bead9@enterprisedb.com
GCC 12 complains that set_stack_base is storing the address of
a local variable in a long-lived pointer. This is an entirely
reasonable warning (indeed, it just helped us find a bug);
but that behavior is intentional here. We can work around it
by using __builtin_frame_address(0) instead of a specific local
variable; that produces an address a dozen or so bytes different,
in my testing, but we don't care about such a small difference.
Maybe someday a compiler lacking that function will start to issue
a similar warning, but we'll worry about that when it happens.
Patch by me, per a suggestion from Andres Freund. Back-patch to
v12, which is as far back as the patch will go without some pain.
(Recently-established project policy would permit a back-patch as
far as 9.2, but I'm disinclined to expend the work until GCC 12
is much more widespread.)
Discussion: https://postgr.es/m/3773792.1645141467@sss.pgh.pa.us
Commit 6a2a70a02 supposed that any platform having <sys/epoll.h>
would also have <sys/signalfd.h>. It turns out there are still a
few people using platforms where that's not so, so we'd better make
a separate configure probe for it. But since it took this long to
notice, I'm content with the decision to not have a separate code
path for epoll-only machines; we'll just fall back to using poll()
for these stragglers.
Per gripe from Gabriela Serventi. Back-patch to v14 where this
code came in.
Discussion: https://postgr.es/m/CAHOHWE-JjJDfcYuLAAEO7Jk07atFAU47z8TzHzg71gbC0aMy=g@mail.gmail.com
The comment for PGAC_READLINE_VARIABLES says "Readline versions < 2.1
don't have rl_completion_append_character". It seems certain that such
versions are extinct in the wild, though; for sure there are none in the
buildfarm. Libedit has had this variable for at least twenty years too.
Also, tab-complete.c's behavior without it is quite unfriendly, since
we'll emit a space even when completion fails; but we've had no
complaints about that.
Therefore, let's assume this variable is always there, and drop the
configure check to save a few build cycles.
Discussion: https://postgr.es/m/147685.1643858911@sss.pgh.pa.us
Try to disable ASLR when building in EXEC_BACKEND mode, to avoid random
memory mapping failures while testing. For developer use only, no
effect on regular builds.
Suggested-by: Andres Freund <andres@anarazel.de>
Tested-by: Bossart, Nathan <bossartn@amazon.com>
Discussion: https://postgr.es/m/20210806032944.m4tz7j2w47mant26%40alap3.anarazel.de
Standardize on xoroshiro128** as our basic PRNG algorithm, eliminating
a bunch of platform dependencies as well as fundamentally-obsolete PRNG
code. In addition, this API replacement will ease replacing the
algorithm again in future, should that become necessary.
xoroshiro128** is a few percent slower than the drand48 family,
but it can produce full-width 64-bit random values not only 48-bit,
and it should be much more trustworthy. It's likely to be noticeably
faster than the platform's random(), depending on which platform you
are thinking about; and we can have non-global state vectors easily,
unlike with random(). It is not cryptographically strong, but neither
are the functions it replaces.
Fabien Coelho, reviewed by Dean Rasheed, Aleksander Alekseev, and myself
Discussion: https://postgr.es/m/alpine.DEB.2.22.394.2105241211230.165418@pseudo
This check was used to accommodate a staggering variety in particular
in the type of the third argument of accept(). This is no longer of
concern on currently supported systems. We can just use socklen_t in
the code and put in a simple check that substitutes int for socklen_t
if it's missing, to cover the few stragglers.
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/3538f4c4-1886-64f2-dcff-aaad8267fb82@enterprisedb.com
Build farm animals running ancient HPUX and Solaris have a non-standard
sigwait() from draft versions of POSIX, so they didn't like commit
7c09d279. To avoid the problem in general, only try to use sigwait() if
it's declared by <signal.h> and matches the expected declaration. To
select the modern declaration on Solaris (even in non-threaded
programs), move -D_POSIX_PTHREAD_SEMANTICS into the right place to
affect all translation units.
Also fix the error checking. Modern sigwait() doesn't set errno.
Thanks to Tom Lane for help with this.
Discussion: https://postgr.es/m/3187588.1626136248%40sss.pgh.pa.us
Apple's mechanism for dealing with functions that are available
in only some OS versions confuses AC_CHECK_FUNCS, and therefore
AC_REPLACE_FUNCS. We can use AC_CHECK_DECLS instead, so long as
we enable -Werror=unguarded-availability-new. This allows people
compiling for macOS to control whether or not preadv/pwritev are
used by setting MACOSX_DEPLOYMENT_TARGET, rather than supplying
a back-rev SDK. (Of course, the latter still works, too.)
James Hilliard
Discussion: https://postgr.es/m/20210122193230.25295-1-james.hilliard1@gmail.com