This is necessary for ActivePerl 5.18 onwards and for Strawberry Perl.
It is not sufficient for 32-bit builds with newer Visual Studio; these
fail with error LINK2026. Back-patch to 9.3 (all supported versions).
Reported by Victor Wagner.
Discussion: https://postgr.es/m/20160326154321.7754ab8f@wagner.wagner.home
Our initial work with int128 neglected alignment considerations, an
oversight that came back to bite us in bug #14897 from Vincent Lachenal.
It is unsurprising that int128 might have a 16-byte alignment requirement;
what's slightly more surprising is that even notoriously lax Intel chips
sometimes enforce that.
Raising MAXALIGN seems out of the question: the costs in wasted disk and
memory space would be significant, and there would also be an on-disk
compatibility break. Nor does it seem very practical to try to allow some
data structures to have more-than-MAXALIGN alignment requirement, as we'd
have to push knowledge of that throughout various code that copies data
structures around.
The only way out of the box is to make type int128 conform to the system's
alignment assumptions. Fortunately, gcc supports that via its
__attribute__(aligned()) pragma; and since we don't currently support
int128 on non-gcc-workalike compilers, we shouldn't be losing any platform
support this way.
Although we could have just done pg_attribute_aligned(MAXIMUM_ALIGNOF) and
called it a day, I did a little bit of extra work to make the code more
portable than that: it will also support int128 on compilers without
__attribute__(aligned()), if the native alignment of their 128-bit-int
type is no more than that of int64.
Add a regression test case that exercises the one known instance of the
problem, in parallel aggregation over a bigint column.
Back-patch of commit 751804998. The code known to be affected only exists
in 9.6 and later, but we do have some stuff using int128 in 9.5, so patch
back to 9.5.
Discussion: https://postgr.es/m/20171110185747.31519.28038@wrigleys.postgresql.org
Upon further review, our Bonjour code doesn't actually work with the
Avahi not-too-compatible compatibility library. While you can get it
to work on non-macOS platforms if you link to Apple's own mDNSResponder
code, there don't seem to be many people who care about that. Leaving in
the AC_SEARCH_LIBS call seems more likely to encourage people to build
broken configurations than to do anything very useful.
Hence, remove the AC_SEARCH_LIBS call and put in a warning comment instead.
Discussion: https://postgr.es/m/2D8331C5-D64F-44C1-8717-63EDC6EAF7EB@brightforge.com
On macOS the relevant functions require no special library, but elsewhere
we need to pull in libdns_sd.
Back-patch to supported branches. No docs change since the docs do not
suggest that this is a Mac-only feature.
Luke Lonergan
Discussion: https://postgr.es/m/2D8331C5-D64F-44C1-8717-63EDC6EAF7EB@brightforge.com
On Linux, shared memory segments created with shm_open() are backed by
swap files created in tmpfs. If the swap file needs to be extended,
but there's no tmpfs space left, you get a very unfriendly SIGBUS trap.
To avoid this, force allocation of the full request size when we create
the segment. This adds a few cycles, but none that we wouldn't expend
later anyway, assuming the request isn't hugely bigger than the actual
need.
Make this code #ifdef __linux__, because (a) there's not currently a
reason to think the same problem exists on other platforms, and (b)
applying posix_fallocate() to an FD created by shm_open() isn't very
portable anyway.
Back-patch to 9.4 where the DSM code came in.
Thomas Munro, per a bug report from Amul Sul
Discussion: https://postgr.es/m/1002664500.12301802.1471008223422.JavaMail.yahoo@mail.yahoo.com
Instead of using a cast to force the constant to be the right width,
assume we can plaster on an L, UL, LL, or ULL suffix as appropriate.
The old approach to this is very hoary, dating from before we were
willing to require compilers to have working int64 types.
This fix makes the PG_INT64_MIN, PG_INT64_MAX, and PG_UINT64_MAX
constants safe to use in preprocessor conditions, where a cast
doesn't work. Other symbolic constants that might be defined using
[U]INT64CONST are likewise safer than before.
Also fix the SIZE_MAX macro to be similarly safe, if we are forced
to provide a definition for that. The test added in commit 2e70d6b5e
happens to do what we want even with the hack "(size_t) -1" definition,
but we could easily get burnt on other tests in future.
Back-patch to all supported branches, like the previous commits.
Discussion: https://postgr.es/m/15883.1504278595@sss.pgh.pa.us
Commit 3c163a7fc's original choice to ignore all #define symbols whose
names begin with underscore turns out to be too simplistic. On Windows,
some Perl installations are built with -D_USE_32BIT_TIME_T, and we must
absorb that or we get the wrong result for sizeof(PerlInterpreter).
This effectively re-reverts commit ef58b87df, which injected that symbol
in a hacky way, making it apply to all of Postgres not just PL/Perl.
More significantly, it did so on *all* 32-bit Windows builds, even when
the Perl build to be used did not select this option; so that it fails
to work properly with some newer Perl builds.
By making this change, we would be introducing an ABI break in 32-bit
Windows builds; but fortunately we have not used type time_t in any
exported Postgres APIs in a long time. So it should be OK, both for
PL/Perl itself and for third-party extensions, if an extension library
is built with a different _USE_32BIT_TIME_T setting than the core code.
Patch by me, based on research by Ashutosh Sharma and Robert Haas.
Back-patch to all supported branches, as commit 3c163a7fc was.
Discussion: https://postgr.es/m/CANFyU97OVQ3+Mzfmt3MhuUm5NwPU=-FtbNH5Eb7nZL9ua8=rcA@mail.gmail.com
LibreSSL defines OPENSSL_VERSION_NUMBER to claim that it is version 2.0.0,
but it doesn't have the functions added in OpenSSL 1.1.0. Add autoconf
checks for the individual functions we need, and stop relying on
OPENSSL_VERSION_NUMBER.
Backport to 9.5 and 9.6, like the patch that broke this. In the
back-branches, there are still a few OPENSSL_VERSION_NUMBER checks left,
to check for OpenSSL 0.9.8 or 0.9.7. I left them as they were - LibreSSL
has all those functions, so they work as intended.
Per buildfarm member curculio.
Discussion: <2442.1473957669@sss.pgh.pa.us>
Changes needed to build at all:
- Check for SSL_new in configure, now that SSL_library_init is a macro.
- Do not access struct members directly. This includes some new code in
pgcrypto, to use the resource owner mechanism to ensure that we don't
leak OpenSSL handles, now that we can't embed them in other structs
anymore.
- RAND_SSLeay() -> RAND_OpenSSL()
Changes that were needed to silence deprecation warnings, but were not
strictly necessary:
- RAND_pseudo_bytes() -> RAND_bytes().
- SSL_library_init() and OpenSSL_config() -> OPENSSL_init_ssl()
- ASN1_STRING_data() -> ASN1_STRING_get0_data()
- DH_generate_parameters() -> DH_generate_parameters()
- Locking callbacks are not needed with OpenSSL 1.1.0 anymore. (Good
riddance!)
Also change references to SSLEAY_VERSION_NUMBER with OPENSSL_VERSION_NUMBER,
for the sake of consistency. OPENSSL_VERSION_NUMBER has existed since time
immemorial.
Fix SSL test suite to work with OpenSSL 1.1.0. CA certificates must have
the "CA:true" basic constraint extension now, or OpenSSL will refuse them.
Regenerate the test certificates with that. The "openssl" binary, used to
generate the certificates, is also now more picky, and throws an error
if an X509 extension is specified in "req_extensions", but that section
is empty.
Backpatch to 9.5 and 9.6, per popular demand. The file structure was
somewhat different in earlier branches, so I didn't bother to go further
than that. In back-branches, we still support OpenSSL 0.9.7 and above.
OpenSSL 0.9.6 should still work too, but I didn't test it. In master, we
only support 0.9.8 and above.
Patch by Andreas Karlsson, with additional changes by me.
Discussion: <20160627151604.GD1051@msg.df7cb.de>
awk's equality-comparison operator is "==" not "=". We got this right
in many places, but not in configure's checks for supported version
numbers of flex and perl. It hadn't been noticed because unsupported
versions are so old as to be basically extinct in the wild, and because
the only consequence is whether or not a WARNING flies by during
configure.
Daniel Gustafsson noted the problem with respect to the test for flex,
I found the other by reviewing other awk calls.
Previously, we included <xlocale.h> only if necessary to get the definition
of type locale_t. According to notes in PGAC_TYPE_LOCALE_T, this is
important because on some versions of glibc that file supplies an
incompatible declaration of locale_t. (This info may be obsolete, because
on my RHEL6 box that seems to be the *only* definition of locale_t; but
there may still be glibc's in the wild for which it's a live concern.)
It turns out though that on FreeBSD and maybe other BSDen, you can get
locale_t from stdlib.h or locale.h but mbstowcs_l() and friends only from
<xlocale.h>. This was leaving us compiling calls to mbstowcs_l() and
friends with no visible prototype, which causes a warning and could
possibly cause actual trouble, since it's not declared to return int.
Hence, adjust the configure checks so that we'll include <xlocale.h>
either if it's necessary to get type locale_t or if it's necessary to
get a declaration of mbstowcs_l().
Report and patch by Aleksander Alekseev, somewhat whacked around by me.
Back-patch to all supported branches, since we have been using
mbstowcs_l() since 9.1.
It emerges that libreadline doesn't notice terminal window size change
events unless they occur while collecting input. This is easy to stumble
over if you resize the window while using a pager to look at query output,
but it can be demonstrated without any pager involvement. The symptom is
that queries exceeding one line are misdisplayed during subsequent input
cycles, because libreadline has the wrong idea of the screen dimensions.
The safest, simplest way to fix this is to call rl_reset_screen_size()
just before calling readline(). That causes an extra ioctl(TIOCGWINSZ)
for every command; but since it only happens when reading from a tty, the
performance impact should be negligible. A more valid objection is that
this still leaves a tiny window during entry to readline() wherein delivery
of SIGWINCH will be missed; but the practical consequences of that are
probably negligible. In any case, there doesn't seem to be any good way to
avoid the race, since readline exposes no functions that seem safe to call
from a generic signal handler --- rl_reset_screen_size() certainly isn't.
It turns out that we also need an explicit rl_initialize() call, else
rl_reset_screen_size() dumps core when called before the first readline()
call.
rl_reset_screen_size() is not present in old versions of libreadline,
so we need a configure test for that. (rl_initialize() is present at
least back to readline 4.0, so we won't bother with a test for it.)
We would need a configure test anyway since libedit's emulation of
libreadline doesn't currently include such a function. Fortunately,
libedit seems not to have any corresponding bug.
Merlin Moncure, adjusted a bit by me
Per buildfarm member anchovy, 2.6.0 exists in the wild now.
Hopefully it works with Postgres; if not, we'll have to do something
about that, but in any case claiming it's "too old" is pretty silly.
With optimizations enabled at least one compiler, clang 3.7, optimized
away the crc intrinsics knowing that the result went on unused and has
no side effects. That can trigger errors in code generation when the
intrinsic is used, as we chose to use the intrinsics without any
additional compiler flag. Return the computed value to prevent that.
With some more pedantic warning flags (-Wold-style-definition) the
configure test failed to recognize the existence of _mm_crc32_u*
intrinsics due to an independent warning in the test because the test
turned on -Werror, but that's not actually needed here.
Discussion: 20150814092039.GH4955@awork2.anarazel.de
Backpatch: 9.5, where the use of crc intrinsics was integrated.
xlc provides "long long" unconditionally at C99-compatible language
levels, and this option provokes a warning. The warning interferes with
"configure" tests that fail in response to any warning. Notably, before
commit 85a2a8903f, it interfered with the
test for -qnoansialias. Back-patch to 9.0 (all supported versions).
Some buildfarm animals are still unhappy. These changes are becoming too
invasive for backpatch, for little benefit. This reverts commits
080c4dab3d and
ce0da62610.
On some Linux systems, "-lrt" exposed pthread-functions, so that linking
with -lrt was seemingly enough to make a program that uses pthreads to
work. However, when linking libpq, the dependency to libpthread was not
marked correctly, so that when an executable was linked with -lpq but
without -pthread, you got errors about undefined pthread_* functions from
libpq.
To fix, test for the flags required to use pthreads earlier in the autoconf
script, before checking any other libraries.
This should fix the failure on buildfarm member shearwater. gharial is also
failing; hopefully this fixes that too although the failure looks somewhat
different.
Our version was different from the upstream version in that we tried to use
all possible pthread-related flags that the compiler accepts, rather than
just the first one that works. That change was made in commit
e48322a6d6, to work-around a bug affecting GCC
versions 3.2 and below (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=8888),
although we didn't realize that it was a GCC bug at the time. We hardly care
about that old GCC versions anymore, so we no longer need that workaround.
This fixes the macro for compilers that print warnings with the chosen
flags. That's pretty annoying on its own right, but it also inconspicuously
disabled thread-safety, because we refused to use any pthread-related flags
if the compiler produced warnings. Max Filippov reported that problem when
linking with uClibc and OpenSSL. The warnings-check was added because the
workaround for the GCC bug caused warnings otherwise, so it's no longer
needed either. We can just use the upstream version as is.
If you really want to compile with GCC version 3.2 or older, you can still
work-around it manually by setting PTHREAD_CFLAGS="-pthread -lpthread"
manually on the configure command line.
Backpatch to 9.5. I don't want to unnecessarily rock the boat on stable
branches, but 9.5 seems like fair game.
Expose PG_VERSION_NUM (e.g., "90600") as a Make variable; but for
consistency with the other Make variables holding similar info,
call the variable just VERSION_NUM not PG_VERSION_NUM.
There was some discussion of making this value available as a pg_config
value as well. However, that would entail substantially more work than
this two-line patch. Given that there was not exactly universal consensus
that we need this at all, let's just do a minimal amount of work for now.
Back-patch of commit a5d489ccb7, so that this
variable is actually useful for its intended purpose sometime before 2020.
Michael Paquier, reviewed by Pavel Stehule
According to recent tests, this case now works fine, so there's no reason
to reject it anymore. (Even if there are still some OpenBSD platforms
in the wild where it doesn't work, removing the check won't break any case
that worked before.)
We can actually remove the entire test that discovers whether libpython
is threaded, since without the OpenBSD case there's no need to know that
at all.
Per report from Davin Potts. Back-patch to all active branches.
By converting to using forward slashes at configure time we avoid
having to repeat the logic anywhere that this is needed, such as
in transforms modules for plpython.
For building PL/Perl, PL/Python, and PL/Tcl, we need a shared library of
libperl, libpython, and libtcl, respectively. Previously, this was
checked in the makefiles, skipping the PL build with a warning if no
shared library was available. Now this is checked in configure, with an
error if no shared library is available.
The previous situation arose because in the olden days, the configure
options --with-perl, --with-python, and --with-tcl controlled whether
frontend interfaces for those languages would be built. The procedural
languages were added later, and shared libraries were often not
available in the beginning. So it was decided skip the builds of the
procedural languages in those cases. The frontend interfaces have since
been removed from the tree, and shared libraries are now available most
of the time, so that setup makes much less sense now.
Also, the new setup allows contrib modules and pgxs users to rely on the
respective PLs being available based on configure flags.
Eliminate the separate 'len' variable from the loops, and also use the 4
byte instruction. This shaves off a few more cycles. Even though this
routine that uses the special SSE 4.2 instructions is much faster than a
generic routine, it's still a hot spot, so let's make it as fast as
possible.
Change the configure test to not test _mm_crc32_u64. That variant is only
available in the 64-bit x86-64 architecture, not in 32-bit x86. Modify
pg_comp_crc32c_sse42 so that it only uses _mm_crc32_u64 on x86-64. With
these changes, the SSE accelerated CRC-32C implementation can also be used
on 32-bit x86 systems.
This also fixes the 32-bit MSVC build.
On gcc and clang, the _mm_crc32_u8 and _mm_crc32_u64 intrinsics are not
defined at all, when not building with -msse4.2. But on icc, they are.
So we cannot assume that if those intrinsics are defined, we can always use
them safely, we might still need the runtime check.
To fix, check if the __SSE_4_2__ preprocessor symbol is defined. That's
supposed to be defined only when the compiler is targeting a processor that
has SSE 4.2 support.
Per buildfarm members fulmar and okapi.
Modern x86 and x86-64 processors with SSE 4.2 support have special
instructions, crc32b and crc32q, for calculating CRC-32C. They greatly
speed up CRC calculation.
Whether the instructions can be used or not depends on the compiler and the
target architecture. If generation of SSE 4.2 instructions is allowed for
the target (-msse4.2 flag on gcc and clang), use them. If they are not
allowed by default, but the compiler supports the -msse4.2 flag to enable
them, compile just the CRC-32C function with -msse4.2 flag, and check at
runtime whether the processor we're running on supports it. If it doesn't,
fall back to the slicing-by-8 algorithm. (With the common defaults on
current operating systems, the runtime-check variant is what you get in
practice.)
Abhijit Menon-Sen, heavily modified by me, reviewed by Andres Freund.
Considering the number of cases in which "unused" command line arguments
are silently ignored by compilers, it's fairly astonishing that anybody
thought this warning was useful; it's certainly nothing but an annoyance
when building Postgres. One such case is that neither gcc nor clang
complain about unrecognized -Wno-foo switches, making it more difficult
to figure out whether the switch does anything than one could wish.
Back-patch to 9.3, which is as far back as the patch applies conveniently
(we'd have to back-patch PGAC_PROG_CC_VAR_OPT to go further, and it doesn't
seem worth that).
We will, for the foreseeable future, not expose 128 bit datatypes to
SQL. But being able to use 128bit math will allow us, in a later patch,
to use 128bit accumulators for some aggregates; leading to noticeable
speedups over using numeric.
So far we only detect a gcc/clang extension that supports 128bit math,
but no 128bit literals, and no *printf support. We might want to expand
this in the future to further compilers; if there are any that that
provide similar support.
Discussion: 544BB5F1.50709@proxel.se
Author: Andreas Karlsson, with significant editorializing by me
Reviewed-By: Peter Geoghegan, Oskari Saarenmaa
