Previously, floating-point output was done by rounding to a specific
decimal precision; by default, to 6 or 15 decimal digits (losing
information) or as requested using extra_float_digits. Drivers that
wanted exact float values, and applications like pg_dump that must
preserve values exactly, set extra_float_digits=3 (or sometimes 2 for
historical reasons, though this isn't enough for float4).
Unfortunately, decimal rounded output is slow enough to become a
noticable bottleneck when dealing with large result sets or COPY of
large tables when many floating-point values are involved.
Floating-point output can be done much faster when the output is not
rounded to a specific decimal length, but rather is chosen as the
shortest decimal representation that is closer to the original float
value than to any other value representable in the same precision. The
recently published Ryu algorithm by Ulf Adams is both relatively
simple and remarkably fast.
Accordingly, change float4out/float8out to output shortest decimal
representations if extra_float_digits is greater than 0, and make that
the new default. Applications that need rounded output can set
extra_float_digits back to 0 or below, and take the resulting
performance hit.
We make one concession to portability for systems with buggy
floating-point input: we do not output decimal values that fall
exactly halfway between adjacent representable binary values (which
would rely on the reader doing round-to-nearest-even correctly). This
is known to be a problem at least for VS2013 on Windows.
Our version of the Ryu code originates from
https://github.com/ulfjack/ryu/ at commit c9c3fb1979, but with the
following (significant) modifications:
- Output format is changed to use fixed-point notation for small
exponents, as printf would, and also to use lowercase 'e', a
minimum of 2 exponent digits, and a mandatory sign on the exponent,
to keep the formatting as close as possible to previous output.
- The output of exact midpoint values is disabled as noted above.
- The integer fast-path code is changed somewhat (since we have
fixed-point output and the upstream did not).
- Our project style has been largely applied to the code with the
exception of C99 declaration-after-statement, which has been
retained as an exception to our present policy.
- Most of upstream's debugging and conditionals are removed, and we
use our own configure tests to determine things like uint128
availability.
Changing the float output format obviously affects a number of
regression tests. This patch uses an explicit setting of
extra_float_digits=0 for test output that is not expected to be
exactly reproducible (e.g. due to numerical instability or differing
algorithms for transcendental functions).
Conversions from floats to numeric are unchanged by this patch. These
may appear in index expressions and it is not yet clear whether any
change should be made, so that can be left for another day.
This patch assumes that the only supported floating point format is
now IEEE format, and the documentation is updated to reflect that.
Code by me, adapting the work of Ulf Adams and other contributors.
References:
https://dl.acm.org/citation.cfm?id=3192369
Reviewed-by: Tom Lane, Andres Freund, Donald Dong
Discussion: https://postgr.es/m/87r2el1bx6.fsf@news-spur.riddles.org.uk
Windows, alone among our supported platforms, likes to emit three-digit
exponent fields even when two digits would do. Adjust such results to
look like the way everyone else does it. Eliminate a bunch of variant
expected-output files that were needed only because of this quirk.
Discussion: https://postgr.es/m/2934.1539122454@sss.pgh.pa.us
This allows out-of-tree PLs and similar code to get access to
definitions needed to work with extension data types.
The following existing modules now install headers: contrib/cube,
contrib/hstore, contrib/isn, contrib/ltree, contrib/seg.
Discussion: https://postgr.es/m/87y3euomjh.fsf%40news-spur.riddles.org.uk
To do this, we only have to remove the compress and decompress support
functions, which have never done anything more than detoasting.
In the wake of commit d3a4f89d8, this results in automatically enabling
index-only scans, since the core code will now know that the stored
representation is the same as the original data (up to detoasting).
The only exciting part of this is that ALTER OPERATOR FAMILY lacks
a way to drop a support function that was declared as being part of
an opclass rather than being loose in the family. For the moment,
we'll hack our way to a solution with a manual update of the pg_depend
entry type, which is what distinguishes the two cases. Perhaps
someday it'll be worth providing a cleaner way to do that, but for
now it seems like a very niche problem.
Note that the underlying C functions remain, to support use of the shared
libraries with older versions of the modules' SQL declarations. Someday
we may be able to remove them, but not soon.
Andrey Borodin, reviewed by me
Discussion: https://postgr.es/m/D0F53A05-4F4A-4DEC-8339-3C069FA0EE11@yandex-team.ru
The lower case spellings are C and C++ standard and are used in most
parts of the PostgreSQL sources. The upper case spellings are only used
in some files/modules. So standardize on the standard spellings.
The APIs for ICU, Perl, and Windows define their own TRUE and FALSE, so
those are left as is when using those APIs.
In code comments, we use the lower-case spelling for the C concepts and
keep the upper-case spelling for the SQL concepts.
Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
Flex generates a lot of functions that are not actually used. In order
to avoid coverage figures being ruined by that, mark up the part of the
.l files where the generated code appears by lcov exclusion markers.
That way, lcov will typically only reported on coverage for the .l file,
which is under our control, but not for the .c file.
Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
The parenthesized style has only been used in a few modules. Change
that to use the style that is predominant across the whole tree.
Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
Reviewed-by: Ryan Murphy <ryanfmurphy@gmail.com>
Don't move parenthesized lines to the left, even if that means they
flow past the right margin.
By default, BSD indent lines up statement continuation lines that are
within parentheses so that they start just to the right of the preceding
left parenthesis. However, traditionally, if that resulted in the
continuation line extending to the right of the desired right margin,
then indent would push it left just far enough to not overrun the margin,
if it could do so without making the continuation line start to the left of
the current statement indent. That makes for a weird mix of indentations
unless one has been completely rigid about never violating the 80-column
limit.
This behavior has been pretty universally panned by Postgres developers.
Hence, disable it with indent's new -lpl switch, so that parenthesized
lines are always lined up with the preceding left paren.
This patch is much less interesting than the first round of indent
changes, but also bulkier, so I thought it best to separate the effects.
Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org
Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
I'd supposed that people would do this manually when creating new operator
classes, but the folly of that was exposed today. The tests seem fast
enough that we can just apply them during the normal regression tests.
contrib/isn fails the checks for lack of complete sets of cross-type
operators. That's a nice-to-have policy rather than a functional
requirement, so leave it as-is, but insert ORDER BY in the query to
ensure consistent cross-platform output.
Discussion: https://postgr.es/m/7076.1480446837@sss.pgh.pa.us
Commit 749a787c5b bumped the extension
version on all of these extensions already, and we haven't had a
release since then, so we can make further changes without bumping the
extension version again. Take this opportunity to mark all of the
functions exported by these modules PARALLEL SAFE -- except for
pg_trgm's set_limit(). Mark that one PARALLEL RESTRICTED, because it
makes a persistent change to a GUC value.
Note that some of the markings added by this commit don't have any
effect; for example, gseg_picksplit() isn't likely to be mentioned
explicitly in a query and therefore it's parallel-safety marking will
never be consulted. But this commit just marks everything for
consistency: if it were somehow used in a query, that would be fine as
far as parallel query is concerned, since it does not consult any
backend-private state, attempt to write data, etc.
Andreas Karlsson, with a few revisions by me.
In commits 9ff60273e3 and dbe2328959 I (tgl) fixed the
signatures of a bunch of contrib's GIN and GIST support functions so that
they would pass validation by the recently-added amvalidate functions.
The backend does not actually consult or check those signatures otherwise,
so I figured this was basically cosmetic and did not require an extension
version bump. However, Alexander Korotkov pointed out that that would
leave us in a pretty messy situation if we ever wanted to redefine those
functions later, because there wouldn't be a unique way to name them.
Since we're going to be bumping these extensions' versions anyway for
parallel-query cleanups, let's take care of this now.
Andreas Karlsson, adjusted for more search-path-safety by me
This reverts commit c8e81afc60.
That turns out to have been based on a faulty diagnosis of why the
VS2015 build was misbehaving. Instead, we need to fix DatumGetBool().
It appears that we can no longer get away with using V0 call convention
for bool-returning functions in newer versions of MSVC. The compiler
seems to generate code that doesn't clear the higher-order bits of the
result register, causing the bool result Datum to often read as "true"
when "false" was intended. This is not very surprising, since the
function thinks it's returning a bool-width result but fmgr_oldstyle
assumes that V0 functions return "char *"; what's surprising is that
that hack worked for so long on so many platforms.
The only functions of this description in core+contrib are in contrib/seg,
which we'd intentionally left mostly in V0 style to serve as a warning
canary if V0 call convention breaks. We could imagine hacking things
so that they're still V0 (we'd have to redeclare the bool-returning
functions as returning some suitably wide integer type, like size_t,
at the C level). But on the whole it seems better to convert 'em to V1.
We can still leave the pointer- and int-returning functions in V0 style,
so that the test coverage isn't gone entirely.
Back-patch to 9.5, since our intention is to support VS2015 in 9.5
and later. There's no SQL-level change in the functions' behavior
so back-patching should be safe enough.
Discussion: <22094.1461273324@sss.pgh.pa.us>
Michael Paquier, adjusted some by me
The restore() function assumed that the result of sprintf() with %e format
would necessarily contain an 'e', which is false: what if the supplied
number is an infinity or NaN? If that did happen, we'd get a
null-pointer-dereference core dump. The case appears impossible currently,
because seg_in() does not accept such values, and there are no seg-creating
functions that would create one. But it seems unwise to rely on it never
happening in future.
Quite aside from that, the code was pretty ugly: it relied on modifying a
static format string when it could use a "*" precision argument, and it
used strtok() entirely gratuitously, and it stripped off trailing spaces
by hand instead of just not asking for them to begin with.
Coverity noticed the potential null pointer dereference (though I wonder
why it didn't complain years ago, since this code is ancient).
Since this is just code cleanup and forestalling a hypothetical future
bug, there seems no need for back-patching.
The conventions specified by the GiST SGML documentation were widely
ignored. For example, the strategy-number argument for "consistent" and
"distance" functions is specified to be a smallint, but most of the
built-in support functions declared it as an integer, and for that matter
the core code passed it using Int32GetDatum not Int16GetDatum. None of
that makes any real difference at runtime, but it's quite confusing for
newcomers to the code, and it makes it very hard to write an amvalidate()
function that checks support function signatures. So let's try to instill
some consistency here.
Another similar issue is that the "query" argument is not of a single
well-defined type, but could have different types depending on the strategy
(corresponding to search operators with different righthand-side argument
types). Some of the functions threw up their hands and declared the query
argument as being of "internal" type, which surely isn't right ("any" would
have been more appropriate); but the majority position seemed to be to
declare it as being of the indexed data type, corresponding to a search
operator with both input types the same. So I've specified a convention
that that's what to do always.
Also, the result of the "union" support function actually must be of the
index's storage type, but the documentation suggested declaring it to
return "internal", and some of the functions followed that. Standardize
on telling the truth, instead.
Similarly, standardize on declaring the "same" function's inputs as
being of the storage type, not "internal".
Also, somebody had forgotten to add the "recheck" argument to both
the documentation of the "distance" support function and all of their
SQL declarations, even though the C code was happily using that argument.
Clean that up too.
Fix up some other omissions in the docs too, such as documenting that
union's second input argument is vestigial.
So far as the errors in core function declarations go, we can just fix
pg_proc.h and bump catversion. Adjusting the erroneous declarations in
contrib modules is more debatable: in principle any change in those
scripts should involve an extension version bump, which is a pain.
However, since these changes are purely cosmetic and make no functional
difference, I think we can get away without doing that.
For upcoming BRIN opclasses, it's convenient to have strategy numbers
defined in a single place. Since there's nothing appropriate, create
it. The StrategyNumber typedef now lives there, as well as existing
strategy numbers for B-trees (from skey.h) and R-tree-and-friends (from
gist.h). skey.h is forced to include stratnum.h because of the
StrategyNumber typedef, but gist.h is not; extensions that currently
rely on gist.h for rtree strategy numbers might need to add a new
A few .c files can stop including skey.h and/or gist.h, which is a nice
side benefit.
Per discussion:
https://www.postgresql.org/message-id/20150514232132.GZ2523@alvh.no-ip.org
Authored by Emre Hasegeli and Álvaro.
(It's not clear to me why bootscanner.l has any #include lines at all.)
This improves on commit bbfd7edae5 by
making two simple changes:
* pg_attribute_noreturn now takes parentheses, ie pg_attribute_noreturn().
Likewise pg_attribute_unused(), pg_attribute_packed(). This reduces
pgindent's tendency to misformat declarations involving them.
* attributes are now always attached to function declarations, not
definitions. Previously some places were taking creative shortcuts,
which were not merely candidates for bad misformatting by pgindent
but often were outright wrong anyway. (It does little good to put a
noreturn annotation where callers can't see it.) In any case, if
we would like to believe that these macros can be used with non-gcc
compilers, we should avoid gratuitous variance in usage patterns.
I also went through and manually improved the formatting of a lot of
declarations, and got rid of excessively repetitive (and now obsolete
anyway) comments informing the reader what pg_attribute_printf is for.
Until now __attribute__() was defined to be empty for all compilers but
gcc. That's problematic because it prevents using it in other compilers;
which is necessary e.g. for atomics portability. It's also just
generally dubious to do so in a header as widely included as c.h.
Instead add pg_attribute_format_arg, pg_attribute_printf,
pg_attribute_noreturn macros which are implemented in the compilers that
understand them. Also add pg_attribute_noreturn and pg_attribute_packed,
but don't provide fallbacks, since they can affect functionality.
This means that external code that, possibly unwittingly, relied on
__attribute__ defined to be empty on !gcc compilers may now run into
warnings or errors on those compilers. But there shouldn't be many
occurances of that and it's hard to work around...
Discussion: 54B58BA3.8040302@ohmu.fi
Author: Oskari Saarenmaa, with some minor changes by me.
Some of the many error messages introduced in 458857cc missed 'FROM
unpackaged'. Also e016b724 and 45ffeb7e forgot to quote extension
version numbers.
Backpatch to 9.1, just like 458857cc which introduced the messages. Do
so because the error messages thrown when the wrong command is copy &
pasted aren't easy to understand.
Prominent binaries already had this metadata. A handful of minor
binaries, such as pg_regress.exe, still lack it; efforts to eliminate
such exceptions are welcome.
Michael Paquier, reviewed by MauMau.
This reverts commit 45b7abe59e.
It turns out that the %name-prefix syntax without "=" does not work
at all in pre-2.4 Bison. We are not prepared to make such a large
jump in minimum required Bison version just to suppress a warning
message in a version hardly any developers are using yet.
When 3.0 gets more popular, we'll figure out a way to deal with this.
In the meantime, BISONFLAGS=-Wno-deprecated is recommendable for
anyone using 3.0 who doesn't want to see the warning.
%name-prefix doesn't use an "=" sign according to the Bison docs, but it
silently accepted one anyway, until Bison 3.0. This was originally a
typo of mine in commit 012abebab1, and we
seem to have slavishly copied the error into all the other grammar files.
Per report from Vik Fearing; analysis by Peter Eisentraut.
Back-patch to all active branches, since somebody might try to build
a back branch with up-to-date tools.
Because of gcc -Wmissing-prototypes, all functions in dynamically
loadable modules must have a separate prototype declaration. This is
meant to detect global functions that are not declared in header files,
but in cases where the function is called via dfmgr, this is redundant.
Besides filling up space with boilerplate, this is a frequent source of
compiler warnings in extension modules.
We can fix that by creating the function prototype as part of the
PG_FUNCTION_INFO_V1 macro, which such modules have to use anyway. That
makes the code of modules cleaner, because there is one less place where
the entry points have to be listed, and creates an additional check that
functions have the right prototype.
Remove now redundant prototypes from contrib and other modules.
These modules used the YYPARSE_PARAM macro, which has been deprecated
by the bison folk since 1.875, and which they finally removed in 3.0.
Adjust the code to use the replacement facility, %parse-param, which
is a much better solution anyway since it allows specification of the
type of the extra parser parameter. We can thus get rid of a lot of
unsightly casting.
Back-patch to all active branches, since somebody might try to build
a back branch with up-to-date tools.
In commit 71450d7fd6, we added code to inform
suitably-intelligent compilers that ereport() doesn't return if the elevel
is ERROR or higher. This patch extends that to elog(), and also fixes a
double-evaluation hazard that the previous commit created in ereport(),
as well as reducing the emitted code size.
The elog() improvement requires the compiler to support __VA_ARGS__, which
should be available in just about anything nowadays since it's required by
C99. But our minimum language baseline is still C89, so add a configure
test for that.
The previous commit assumed that ereport's elevel could be evaluated twice,
which isn't terribly safe --- there are already counterexamples in xlog.c.
On compilers that have __builtin_constant_p, we can use that to protect the
second test, since there's no possible optimization gain if the compiler
doesn't know the value of elevel. Otherwise, use a local variable inside
the macros to prevent double evaluation. The local-variable solution is
inferior because (a) it leads to useless code being emitted when elevel
isn't constant, and (b) it increases the optimization level needed for the
compiler to recognize that subsequent code is unreachable. But it seems
better than not teaching non-gcc compilers about unreachability at all.
Lastly, if the compiler has __builtin_unreachable(), we can use that
instead of abort(), resulting in a noticeable code savings since no
function call is actually emitted. However, it seems wise to do this only
in non-assert builds. In an assert build, continue to use abort(), so that
the behavior will be predictable and debuggable if the "impossible"
happens.
These changes involve making the ereport and elog macros emit do-while
statement blocks not just expressions, which forces small changes in
a few call sites.
Andres Freund, Tom Lane, Heikki Linnakangas
Numerous flex and bison make rules have appeared in the source tree
over time, and they are all virtually identical, so we can replace
them by pattern rules with some variables for customization.
Users of pgxs will also be able to benefit from this.
We have seen one too many reports of people trying to use 9.1 extension
files in the old-fashioned way of sourcing them in psql. Not only does
that usually not work (due to failure to substitute for MODULE_PATHNAME
and/or @extschema@), but if it did work they'd get a collection of loose
objects not an extension. To prevent this, insert an \echo ... \quit
line that prints a suitable error message into each extension script file,
and teach commands/extension.c to ignore lines starting with \echo.
That should not only prevent any adverse consequences of loading a script
file the wrong way, but make it crystal clear to users that they need to
do it differently now.
Tom Lane, following an idea of Andrew Dunstan's. Back-patch into 9.1
... there is not going to be much value in this if we wait till 9.2.
Added a new option --extra-install to pg_regress to arrange installing
the respective contrib directory into the temporary installation.
This is currently not yet supported for Windows MSVC builds.
Updated the .gitignore files for contrib modules to ignore the
leftovers of a temp-install check run.
Changed the exit status of "make check" in a pgxs build (which still
does nothing) to 0 from 1.
Added "make check" in contrib to top-level "make check-world".
This warning is new in gcc 4.6 and part of -Wall. This patch cleans
up most of the noise, but there are some still warnings that are
trickier to remove.
It was never terribly consistent to use OR REPLACE (because of the lack of
comparable functionality for data types, operators, etc), and
experimentation shows that it's now positively pernicious in the extension
world. We really want a failure to occur if there are any conflicts, else
it's unclear what the extension-ownership state of the conflicted object
ought to be. Most of the time, CREATE EXTENSION will fail anyway because
of conflicts on other object types, but an extension defining only
functions can succeed, with bad results.
This isn't fully tested as yet, in particular I'm not sure that the
"foo--unpackaged--1.0.sql" scripts are OK. But it's time to get some
buildfarm cycles on it.
sepgsql is not converted to an extension, mainly because it seems to
require a very nonstandard installation process.
Dimitri Fontaine and Tom Lane
This patch replaces Guttman's generalized split method with a simple
sort-by-center-points algorithm. Since the data is only one-dimensional
we don't really need the slow and none-too-stable Guttman method.
This is in part a bug fix, since seg has the same size_alpha versus
size_beta typo that was recently fixed in contrib/cube. It seems
prudent to apply this rather aggressive fix only in HEAD, though.
Back branches will just get the typo fix.
Alexander Korotkov, reviewed by Yeb Havinga
source directory even for out-of-tree builds. They are now alsl built in
the build tree. This should be more convenient for certain developers'
workflows, and shouldn't really break anything else.
Andrew Gierth