In commit 71450d7f, 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.

The latter was already the dominant use, and it's preferable because
in C the convention is that intXX means XX bits.  Therefore, allowing
mixed use of int2, int4, int8, int16, int32 is obviously confusing.

Remove the typedefs for int2 and int4 for now.  They don't seem to be
widely used outside of the PostgreSQL source tree, and the few uses
can probably be cleaned up by the time this ships.

These are not touched by pgindent, so clean them up a bit manually.

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.

walsender.h should depend on xlog.h, not vice versa.  (Actually, the
inclusion was circular until a couple hours ago, which was even sillier;
but Bruce broke it in the expedient rather than logically correct
direction.)  Because of that poor decision, plus blind application of
pgrminclude, we had a situation where half the system was depending on
xlog.h to include such unrelated stuff as array.h and guc.h.  Clean up
the header inclusion, and manually revert a lot of what pgrminclude had
done so things build again.

This episode reinforces my feeling that pgrminclude should not be run
without adult supervision.  Inclusion changes in header files in particular
need to be reviewed with great care.  More generally, it'd be good if we
had a clearer notion of module layering to dictate which headers can sanely
include which others ... but that's a big task for another day.

builfarm member.

include dependencies.

Modify pgcompinclude to skip a common fcinfo error.

This is recommended in the flex manual, and there seems no good reason
not to use it everywhere.

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".

Backport to 9.0, we're not supporting this compiler on earlier releases.

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 applies the fix for bug #5784 to remaining places where we wish
to reject nulls in user-supplied arrays.  In all these places, there's
no reason not to allow a null bitmap to be present, so long as none of
the current elements are actually null.

I did not change some other places where we are looking at system catalog
entries or aggregate transition values, as the presence of a null bitmap
in such an array would be suspicious.

Alexander Korotkov

Also do some further work in the back branches, where quite a bit wasn't
covered by Magnus' original back-patch.

Two of these were pointed out by Erik Rijkers; the rest I found.

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.

(Note: GiST penalty functions could possibly be non-strict, but none are at
present.)

provided by Andrew.

during parsing.  Formerly the parser's stack was allocated with malloc
and so wouldn't be reclaimed; this patch makes it use palloc instead,
so that flushing the current context will reclaim the memory.  Per
Marko Kreen.

There are still some weak spots around JOIN USING and relation alias lists,
but most errors reported within backend/parser/ now have locations.

change build system to use only Bison.  Simplify build rules, make file names
uniform.  Don't build the token table header file where it is not needed.

warnings.  Peter did this for core awhile ago but evidently missed
contrib.

calling convention.  cube_inter and cube_distance could attempt to pfree
their input arguments, and cube_dim returned a value from a struct it
might have just pfree'd (which would only really cause a problem in a
debug build, but it's still wrong).  Per bug #4208 and additional code
reading.

In HEAD and 8.3, I also made a batch of cosmetic changes to bring these
functions into line with the preferred coding style for V1 functions,
ie declare and fetch all the arguments at the top so readers can easily
see what they are.

"consistent" functions, and remove pg_amop.opreqcheck, as per recent
discussion.  The main immediate benefit of this is that we no longer need
8.3's ugly hack of requiring @@@ rather than @@ to test weight-using tsquery
searches on GIN indexes.  In future it should be possible to optimize some
other queries better than is done now, by detecting at runtime whether the
index match is exact or not.

Tom Lane, after an idea of Heikki's, and with some help from Teodor.

	remove transactions
	use create or replace function
	make formatting consistent
	set search patch on first line

Add documentation on modifying *.sql to set the search patch, and
mention that major upgrades should still run the installation scripts.

Some of these issues were spotted by Tom today.

or will never be converted.

Found by running opr_sanity on contrib modules.

installations whose pg_config program does not appear first in the PATH.
Per gripe from Eddie Stanley and subsequent discussions with Fabien Coelho
and others.

from the other string-category types; this eliminates a lot of surprising
interpretations that the parser could formerly make when there was no directly
applicable operator.

Create a general mechanism that supports casts to and from the standard string
types (text,varchar,bpchar) for *every* datatype, by invoking the datatype's
I/O functions.  These new casts are assignment-only in the to-string direction,
explicit-only in the other, and therefore should create no surprising behavior.
Remove a bunch of thereby-obsoleted datatype-specific casting functions.

The "general mechanism" is a new expression node type CoerceViaIO that can
actually convert between *any* two datatypes if their external text
representations are compatible.  This is more general than needed for the
immediate feature, but might be useful in plpgsql or other places in future.

This commit does nothing about the issue that applying the concatenation
operator || to non-text types will now fail, often with strange error messages
due to misinterpreting the operator as array concatenation.  Since it often
(not always) worked before, we should either make it succeed or at least give
a more user-friendly error; but details are still under debate.

Peter Eisentraut and Tom Lane