has been reinvented about four different times throughout history (aix,
cygwin, win32, darwin/linux) and a lot of the concepts are actually shared,
which the code now shows better.

doesn't exist yet.

So only rebuild when a makefile changes (which presumably defines the
file list somewhere), and only touch the file if an object changed. The
touch is necessary so the parent make knows something changed and
ultimately rebuilds postgres.

only once in Makefile.shlib and not in four copies.

values into \nnn octal escape sequences.  When the database encoding is
multibyte this is *necessary* to avoid generating invalidly encoded text.
Even in a single-byte encoding, the old behavior seems very hazardous ---
consider for example what happens if the text is transferred to another
database with a different encoding.  Decoding would then yield some other
bytea value than what was encoded, which is surely undesirable.  Per gripe
from Hernan Gonzalez.

Backpatch to 8.3, but not further.  This is a bit of a judgment call, but I
make it on these grounds: pre-8.3 we don't really have much encoding safety
anyway because of the convert() function family, and we would also have much
higher risk of breaking existing apps that may not be expecting this behavior.
8.3 is still new enough that we can probably get away with making this change
in the function's behavior.

(then it means 2000 AD).  Formerly we silently interpreted this as 1 BC,
which at best is unwarranted familiarity with the implementation.
It's barely possible that some app somewhere expects the old behavior,
though, so we won't back-patch this into existing release branches.

Formerly, DecodeDate attempted to verify the day-of-the-month exactly, but
it was under the misapprehension that it would know whether we were looking
at a BC year or not.  In reality this check can't be made until the calling
function (eg DecodeDateTime) has processed all the fields.  So, split the
BC adjustment and validity checks out into a new function ValidateDate that
is called only after processing all the fields.  In passing, this patch
makes DecodeTimeOnly work for BC inputs, which it never did before.

(The historical veracity of all this is nonexistent, of course, but if
we're going to say we support proleptic Gregorian calendar then we should
do it correctly.  In any case the unpatched code is broken because it could
emit dates that it would then reject on re-inputting.)

Per report from Bernd Helmle.  Back-patch as far as 8.0; in 7.x we were
not using our own calendar support and so this seems a bit too risky
to put into 7.4.

SUBSYS.o step and allow for better optimization by the linker.

Instead of partial linking into SUBSYS.o, the list of object files is
assembled in objfiles.txt files that are expanded when the final
linking is done.

Because we are not yet sure how long command lines different platforms
can handle, the old way of linking is still available, by defining the
make variable PARTIAL_LINKING (e.g., make all PARTIAL_LINKING=1).  If
we determine that this is necessary for some platforms, then we will
document this in a more prominent place.

versions don't handle long options the way we want.  Per Zdenek Kotala.

platforms this works, but on some it crashes.  Zdenek Kotala

represented as "char ...[4]" not "int32".  Since the length word is never
supposed to be accessed via this struct member anyway, this won't break
any existing code that is following the rules.  The advantage is that C
compilers will no longer assume that a pointer to struct varlena is
word-aligned, which prevents incorrect optimizations in TOAST-pointer
access and perhaps other places.  gcc doesn't seem to do this (at least
not at -O2), but the problem is demonstrable on some other compilers.

I changed struct inet as well, but didn't bother to touch a lot of other
struct definitions in which it wouldn't make any difference because there
were other fields forcing int alignment anyway.  Hopefully none of those
struct definitions are used for accessing unaligned Datums.

make it a bit clearer what it is, and get rid of duplicate definitions
in initdb and pg_ctl.

programs: use puts with a compile-time-constant string.

non-default settings for the postmaster's port number.  The code to parse
command line options and postgresql.conf entries wasn't quite right about
whitespace or quotes, and it was coded in a not-very-readable way too.
Per bug #3969 from Itagaki Takahiro, though this is more extensive than his
proposed patch (which fixed only the whitespace problem).
This code has been broken since it was put in in 8.0, so patch all the way
back.

OID or new relfilenode.  If the existing OIDs are sufficiently densely
populated, this could take a long time (perhaps even be an infinite loop),
so it seems wise to allow the system to respond to a cancel interrupt here.
Per a gripe from Jacky Leng.

Backpatch as far as 8.1.  Older versions just fail on OID collision,
instead of looping.

Per gripe from Clodoaldo Pinto Neto on
Message-ID: <a595de7a0801060326qbfc790ax2a60573043c2e2be@mail.gmail.com>

from Jaime Casanova.

port files, which obviously didn't compile)

and RI_FKey_keyequal_upd_fk, as well as no-longer-needed calls of
ri_BuildQueryKeyFull.  Aside from saving a few cycles, this avoids needless
deadlock risks when an update is not changing the columns that participate
in an RI constraint.  Per a gripe from Alexey Nalbat.

Back-patch to 8.3.  Earlier releases did have a need to open the other
relation due to the way in which they retrieved information about the RI
constraint, so this problem unfortunately can't easily be improved pre-8.3.

Tom Lane and Stephan Szabo

reorganize code for NetBSD/BSDi port/fseeko.c usage, and make code more
modular.

- Changed INFORMIX mode symbol definition yet again because the old way didn't work on NetBSD. Hopefully this one does.

- Change configure.in to use Autoconf 2.61 and update generated files.
- Update build system and documentation to support now directory variables
  offered by Autoconf 2.61.
- Replace usages of PGAC_CHECK_ALIGNOF by AC_CHECK_ALIGNOF, now available
  in Autoconf 2.61.
- Drop our patched version of AC_C_INLINE, as Autoconf now has the change.

on Linux.

data structures and backend internal APIs.  This solves problems we've seen
recently with inconsistent layout of pg_control between machines that have
32-bit time_t and those that have already migrated to 64-bit time_t.  Also,
we can get out from under the problem that Windows' Unix-API emulation is not
consistent about the width of time_t.

There are a few remaining places where local time_t variables are used to hold
the current or recent result of time(NULL).  I didn't bother changing these
since they do not affect any cross-module APIs and surely all platforms will
have 64-bit time_t before overflow becomes an actual risk.  time_t should
be avoided for anything visible to extension modules, however.

<
> * -Allow AS in "SELECT col AS label" to be optional in certain cases
>
< * Allow AS in "SELECT col AS label" to be optional (not wanted)

outside the 32-bit-time_t range.  Also, refer to Olson's tz database
as the 'zoneinfo' database, a name that upstream sometimes uses, not
'zic database' which they never use.

this adds support for 64-bit tzdata files, which is needed to support DST
calculations beyond 2038.  Add a regression test case to give some minimal
confidence that that really works.

Heikki Linnakangas

log_checkpoints in 8.3.