A PostgreSQL release tarball contains a number of prebuilt files, in
particular files produced by bison, flex, perl, and well as html and
man documentation. We have done this consistent with established
practice at the time to not require these tools for building from a
tarball. Some of these tools were hard to get, or get the right
version of, from time to time, and shipping the prebuilt output was a
convenience to users.
Now this has at least two problems:
One, we have to make the build system(s) work in two modes: Building
from a git checkout and building from a tarball. This is pretty
complicated, but it works so far for autoconf/make. It does not
currently work for meson; you can currently only build with meson from
a git checkout. Making meson builds work from a tarball seems very
difficult or impossible. One particular problem is that since meson
requires a separate build directory, we cannot make the build update
files like gram.h in the source tree. So if you were to build from a
tarball and update gram.y, you will have a gram.h in the source tree
and one in the build tree, but the way things work is that the
compiler will always use the one in the source tree. So you cannot,
for example, make any gram.y changes when building from a tarball.
This seems impossible to fix in a non-horrible way.
Second, there is increased interest nowadays in precisely tracking the
origin of software. We can reasonably track contributions into the
git tree, and users can reasonably track the path from a tarball to
packages and downloads and installs. But what happens between the git
tree and the tarball is obscure and in some cases non-reproducible.
The solution for both of these issues is to get rid of the step that
adds prebuilt files to the tarball. The tarball now only contains
what is in the git tree (*). Getting the additional build
dependencies is no longer a problem nowadays, and the complications to
keep these dual build modes working are significant. And of course we
want to get the meson build system working universally.
This commit removes the make distprep target altogether. The make
dist target continues to do its job, it just doesn't call distprep
anymore.
(*) - The tarball also contains the INSTALL file that is built at make
dist time, but not by distprep. This is unchanged for now.
The make maintainer-clean target, whose job it is to remove the
prebuilt files in addition to what make distclean does, is now just an
alias to make distprep. (In practice, it is probably obsolete given
that git clean is available.)
The following programs are now hard build requirements in configure
(they were already required by meson.build):
- bison
- flex
- perl
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/flat/e07408d9-e5f2-d9fd-5672-f53354e9305e@eisentraut.org
parse.pl and check_rules.pl used "no warnings 'uninitialized'",
which doesn't seem like it measures up to current project standards.
Removing that shows that it was hiding various places that accessed
off the end of an array, which are easily protected by minor logic
adjustments. There's no change in the script results.
While here, improve the Makefile rule that invokes these scripts.
It neglected to depend on check_rules.pl, so that editing that file
didn't result in re-running the check; and it ran check_rules.pl
after building preproc.y, so that if check_rules.pl did fail the
next "make" attempt would just bypass it. check_rules.pl failures
are sufficiently un-heard-of that I don't feel a need to back-patch
this.
Discussion: https://postgr.es/m/838180.1658181982@sss.pgh.pa.us
This is in preparation for building postgres with meson / ninja.
When building with meson, commands are run at the root of the build tree. Add
an option to put build output into the appropriate place. This can be utilized
by src/tools/msvc/ for a minor simplification, which also provides some
coverage for the new option.
Add option to generate a timestamp for check_rules.pl, so that proper
dependencies on it having been run can be generated.
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Discussion: https://postgr.es/m/5e216522-ba3c-f0e6-7f97-5276d0270029@enterprisedb.com
When maintaining or merging patches, one of the most common sources
for conflicts are the list of objects in makefiles. Especially when
the split across lines has been changed on both sides, which is
somewhat common due to attempting to stay below 80 columns, those
conflicts are unnecessarily laborious to resolve.
By splitting, and alphabetically sorting, OBJS style lines into one
object per line, conflicts should be less frequent, and easier to
resolve when they still occur.
Author: Andres Freund
Discussion: https://postgr.es/m/20191029200901.vww4idgcxv74cwes@alap3.anarazel.de
This addresses a couple of issues in the code:
- Typos and inconsistencies in comments and function declarations.
- Removal of unreferenced function declarations.
- Removal of unnecessary compile flags.
- A cleanup error in regressplans.sh.
Author: Alexander Lakhin
Discussion: https://postgr.es/m/0c991fdf-2670-1997-c027-772a420c4604@gmail.com
We've been speculating for a long time that hash-based keyword lookup
ought to be faster than binary search, but up to now we hadn't found
a suitable tool for generating the hash function. Joerg Sonnenberger
provided the inspiration, and sample code, to show us that rolling our
own generator wasn't a ridiculous idea. Hence, do that.
The method used here requires a lookup table of approximately 4 bytes
per keyword, but that's less than what we saved in the predecessor commit
afb0d0712, so it's not a big problem. The time savings is indeed
significant: preliminary testing suggests that the total time for raw
parsing (flex + bison phases) drops by ~20%.
Patch by me, but it owes its existence to Joerg Sonnenberger;
thanks also to John Naylor for review.
Discussion: https://postgr.es/m/20190103163340.GA15803@britannica.bec.de
Previously, ScanKeywordLookup was passed an array of string pointers.
This had some performance deficiencies: the strings themselves might
be scattered all over the place depending on the compiler (and some
quick checking shows that at least with gcc-on-Linux, they indeed
weren't reliably close together). That led to very cache-unfriendly
behavior as the binary search touched strings in many different pages.
Also, depending on the platform, the string pointers might need to
be adjusted at program start, so that they couldn't be simple constant
data. And the ScanKeyword struct had been designed with an eye to
32-bit machines originally; on 64-bit it requires 16 bytes per
keyword, making it even more cache-unfriendly.
Redesign so that the keyword strings themselves are allocated
consecutively (as part of one big char-string constant), thereby
eliminating the touch-lots-of-unrelated-pages syndrome. And get
rid of the ScanKeyword array in favor of three separate arrays:
uint16 offsets into the keyword array, uint16 token codes, and
uint8 keyword categories. That reduces the overhead per keyword
to 5 bytes instead of 16 (even less in programs that only need
one of the token codes and categories); moreover, the binary search
only touches the offsets array, further reducing its cache footprint.
This also lets us put the token codes somewhere else than the
keyword strings are, which avoids some unpleasant build dependencies.
While we're at it, wrap the data used by ScanKeywordLookup into
a struct that can be treated as an opaque type by most callers.
That doesn't change things much right now, but it will make it
less painful to switch to a hash-based lookup method, as is being
discussed in the mailing list thread.
Most of the change here is associated with adding a generator
script that can build the new data structure from the same
list-of-PG_KEYWORD header representation we used before.
The PG_KEYWORD lists that plpgsql and ecpg used to embed in
their scanner .c files have to be moved into headers, and the
Makefiles have to be taught to invoke the generator script.
This work is also necessary if we're to consider hash-based lookup,
since the generator script is what would be responsible for
constructing a hash table.
Aside from saving a few kilobytes in each program that includes
the keyword table, this seems to speed up raw parsing (flex+bison)
by a few percent. So it's worth doing even as it stands, though
we think we can gain even more with a follow-on patch to switch
to hash-based lookup.
John Naylor, with further hacking by me
Discussion: https://postgr.es/m/CAJVSVGXdFVU2sgym89XPL=Lv1zOS5=EHHQ8XWNzFL=mTXkKMLw@mail.gmail.com
It's important for link commands to list *.o input files before -l
switches for libraries, as library code may not get pulled into the link
unless referenced by an earlier command-line entry. This is certainly
necessary for static libraries (.a style). Apparently on some platforms
it is also necessary for shared libraries, as reported by Donald Dong.
We often put -l switches for within-tree libraries into LDFLAGS, meaning
that link commands that list *.o files after LDFLAGS are hazardous.
Most of our link commands got this right, but a few did not. In
particular, places that relied on gmake's default implicit link rule
failed, because that puts LDFLAGS first. Fix that by overriding the
built-in rule with our own. The implicit link rules in
src/makefiles/Makefile.* for single-.o-file shared libraries mostly
got this wrong too, so fix them. I also changed the link rules for the
backend and a couple of other places for consistency, even though they
are not (currently) at risk because they aren't adding any -l switches
to LDFLAGS.
Arguably, the real problem here is that we're abusing LDFLAGS by
putting -l switches in it and we should stop doing that. But changing
that would be quite invasive, so I'm not eager to do so.
Perhaps this is a candidate for back-patching, but so far it seems
that problems can only be exhibited in test code we don't normally
build, and at least some of the problems are new in HEAD anyway.
So I'll refrain for now.
Donald Dong and Tom Lane
Discussion: https://postgr.es/m/CAKABAquXn-BF-vBeRZxhzvPyfMqgGuc74p8BmQZyCFDpyROBJQ@mail.gmail.com
Re-making ecpglib's typename.o is dangerous because another make thread
could be doing that at the same time. While we've not heard field
complaints traceable to this, it seems inevitable that it'd bite someone
eventually. Instead, symlink typename.c into the preproc directory and
recompile it there. That file is small enough that compiling it twice
isn't much of a penalty. Furthermore, this way we get a .o file that's
made without shlib CFLAGS, which seems cleaner.
This requires adding more stuff to the module's -I list. The MSVC
aspect of that is untested, but I'm sure the buildfarm will tell me
if I got it wrong.
Per a suggestion from Peter Eisentraut. Although this is theoretically
a bug fix, the lack of field reports makes me feel we needn't back-patch.
Discussion: https://postgr.es/m/31364.1543511708@sss.pgh.pa.us
GNUmakefile.in defined a macro "garbage" that seems to have been meant
as a suitable target for automatic "rm -rf" treatment, but it isn't
actually used anywhere (and indeed never was, AFAICT).
Moreover, we have concluded that the Makefiles shouldn't take it upon
themselves to remove files that aren't expected by-products of building,
so that doing anything like that would be against project policy anyway.
Hence, just remove the macro.
Grepping around finds another violation of that policy in ecpg/preproc,
so clean that up too.
Daniel Gustafsson (ecpg change by me)
Discussion: https://postgr.es/m/AFBEF63E-E19D-4EBB-9F08-4617CDC751ED@yesql.se
For years, our makefiles have correctly observed that "there is no correct
way to write a rule that generates two files". However, what we did is to
provide empty rules that "generate" the secondary output files from the
primary one, and that's not right either. Depending on the details of
the creating process, the primary file might end up timestamped later than
one or more secondary files, causing subsequent make runs to consider the
secondary file(s) out of date. That's harmless in a plain build, since
make will just re-execute the empty rule and nothing happens. But it's
fatal in a VPATH build, since make will expect the secondary file to be
rebuilt in the build directory. This would manifest as "file not found"
failures during VPATH builds from tarballs, if we were ever unlucky enough
to ship a tarball with apparently out-of-date secondary files. (It's not
clear whether that has ever actually happened, but it definitely could.)
To ensure that secondary output files have timestamps >= their primary's,
change our makefile convention to be that we provide a "touch $@" action
not an empty rule. Also, make sure that this rule actually gets invoked
during a distprep run, else the hazard remains.
It's been like this a long time, so back-patch to all supported branches.
In HEAD, I skipped the changes in src/backend/catalog/Makefile, because
those rules are due to get replaced soon in the bootstrap data format
patch, and there seems no need to create a merge issue for that patch.
If for some reason we fail to land that patch in v11, we'll need to
back-fill the changes in that one makefile from v10.
Discussion: https://postgr.es/m/18556.1521668179@sss.pgh.pa.us
Once upon a time, it made sense for the ecpg preprocessor to have its
own version number, because it used a manually-maintained grammar that
wasn't always in sync with the core grammar. But those days are
thankfully long gone, leaving only a maintenance nuisance behind.
Let's use the PG v10 version numbering changeover as an excuse to get
rid of the ecpg version number and just have ecpg identify itself by
PG_VERSION. From the user's standpoint, ecpg will go from "4.12" in
the 9.6 branch to "10" in the 10 branch, so there's no failure of
monotonicity.
Discussion: <1471332659.4410.67.camel@postgresql.org>
Now that we have src/common/ for code shared between frontend and backend,
we can get rid of (most of) the klugy ways that the keyword table and
keyword lookup code were formerly shared between different uses.
This is a first step towards a more general plan of getting rid of
special-purpose kluges for sharing code in src/bin/.
I chose to merge kwlookup.c back into keywords.c, as it once was, and
always has been so far as keywords.h is concerned. We could have
kept them separate, but there is noplace that uses ScanKeywordLookup
without also wanting access to the backend's keyword list, so there
seems little point.
ecpg is still a bit weird, but at least now the trickiness is documented.
I think that the MSVC build script should require no adjustments beyond
what's done here ... but we'll soon find out.
Now that we know about the %top{} trick, we can revert to building flex
lexers as separate .o files. This is worth doing for a couple of reasons
besides sheer cleanliness. We can narrow the scope of the -Wno-error flag
that's forced on scan.c. Also, since these grammar and lexer files are
so large, splitting them into separate build targets should have some
advantages in build speed, particularly in parallel or ccache'd builds.
We have quite a few other .l files that could be changed likewise, but the
above arguments don't apply to them, so the benefit of fixing them seems
pretty minimal. Leave the rest for some other day.
This is to see if it will stop intermittent build failures on buildfarm
member okapi. We know that gmake 3.82 has some problems with sometimes
not honoring dependencies in parallel builds, and it seems likely that
this is more of the same. Since the vast bulk of the work in the preproc
directory is associated with creating preproc.c and then preproc.o,
parallelism buys us hardly anything here anyway.
Also, make both this .NOTPARALLEL and the one previously added in
interfaces/ecpg/Makefile be conditional on "ifeq ($(MAKE_VERSION),3.82)".
The known bug in gmake is fixed upstream and should not be present in
3.83 and up, and there's no reason to think it affects older releases.
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.
This includes fixing the MSVC copy of ecpg/preproc's version info, which
seems to have been overlooked repeatedly. Can't we fix that so there are
not two copies??
Replace for loops in makefiles with proper dependencies. Parallel
make can now span across directories. Also, make -k and make -q work
properly.
GNU make 3.80 or newer is now required.
linking both executables and shared libraries, and we add on LDFLAGS_EX when
linking executables or LDFLAGS_SL when linking shared libraries. This
provides a significantly cleaner way of dealing with link-time switches than
the former behavior. Also, make sure that the various platform-specific
%.so: %.o rules incorporate LDFLAGS and LDFLAGS_SL; most of them missed that
before. (I did not add these variables for the platforms that invoke $(LD)
directly, however. It's not clear if we can do that safely, since for the
most part we assume these variables use CC command-line syntax.)
Per gripe from Aaron Swenson and subsequent investigation.
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.
Update install-sh to that from Autoconf 2.63, plus our Darwin-specific
changes (which I simplified a bit). install-sh is now able to install
multiple files in one run, so we could simplify our makefiles sometime.
install-sh also now has a -d option to create directories, so we don't need
mkinstalldirs anymore.
Use AC_PROG_MKDIR_P in configure.in, so we can use mkdir -p when available
instead of install-sh -d. For consistency with the rest of the world,
the corresponding make variable has been renamed from $(mkinstalldirs) to
$(MKDIR_P).
Peter Eisentraut
Bruce Momjian
Tom Lane
Andres Freund
Michael Paquier
Peter Eisentraut
Michael Meskes
Magnus Hagander