Horton

Re: master make check fails on Solaris 10

Tom Lane <tgl@sss.pgh.pa.us>

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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Marina Polyakova <m.polyakova@postgrespro.ru>
Cc: Andres Freund <andres@anarazel.de>, pgsql-hackers@postgresql.org, Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: 2018-01-13T18:10:55Z
Lists: pgsql-hackers 
Marina Polyakova <m.polyakova@postgrespro.ru> writes:
> On 12-01-2018 21:00, Tom Lane wrote:
>> Hm ... so apparently, that compiler has bugs in handling nondefault
>> alignment specs.  You said upthread it was gcc, but what version
>> exactly?

> This is 5.2.0:

Ugh ... protosciurus has 3.4.3, but I see that configure detects that
as *not* having __int128.  Probably what's happening on your machine
is that gcc knows __int128 but generates buggy code for it when an
alignment spec is given.  So that's unfortunate, but it's not really
a regression from 3.4.3.

I'm not sure there's much we can do about this.  Dropping the use
of the alignment spec isn't a workable option.  If there were a
simple way for configure to detect that the compiler generates bad
code for that, we could have it do so and reject use of __int128,
but it'd be up to you to come up with a workable test.

In the end this might just be an instance of the old saw about
avoiding dot-zero releases.  Have you tried a newer gcc?
(Digging in their bugzilla finds quite a number of __int128 bugs
fixed in 5.4.x, though none look to be specifically about
misaligned data.)

Also, if it still happens with current gcc on that hardware,
there'd be grounds for a new bug report to them.

			regards, tom lane

Commits

  1. Extend configure's __int128 test to check for a known gcc bug.

  2. Reorder C includes

  3. Ability to advance replication slots

  4. doc: add JSON acronym

  5. Expression evaluation based aggregate transition invocation.

  6. Change some bogus PageGetLSN calls to BufferGetLSNAtomic

  7. Prevent int128 from requiring more than MAXALIGN alignment.

  8. Rearrange c.h to create a "compiler characteristics" section.

  9. Make OWNER TO subcommand mention consistent