Обсуждение: pgsql-server/src/makefiles Makefile.linux

CVSROOT:    /cvsroot
Module name:    pgsql-server
Changes by:    tgl@developer.postgresql.org    03/05/19 13:51:01

Modified files:
    src/makefiles  : Makefile.linux

Log message:
    Use -fPIC on Sparc, per Tom Callaway.

Tom Lane writes:

>     Use -fPIC on Sparc, per Tom Callaway.

Then we might as well use -fPIC everywhere all the time, because if it
happens on Linux/Sparc then it's bound to happen on all platforms where it
makes a difference.  (And where it doesn't make a difference, there's no
harm.)

--
Peter Eisentraut   peter_e@gmx.net

Peter Eisentraut <peter_e@gmx.net> writes:
> Tom Lane writes:
>> Use -fPIC on Sparc, per Tom Callaway.

> Then we might as well use -fPIC everywhere all the time, because if it
> happens on Linux/Sparc then it's bound to happen on all platforms where it
> makes a difference.

No, it's not: Sparc has the smallest -fpic GOT size limit of all
platforms, and apparently it needs to generate more GOT entries than
others, too.

I'm not actually convinced that Sparc has a real need for -fPIC, either,
since Lamar could not reproduce Tom's problem, and the GOT sizes I can
measure on x86 are an order of magnitude smaller than the Sparc limit.
I pushed out the change quickly because of the impending 7.3.3 deadline,
but I'm more than half inclined to revert it.

I have verified that HPPA doesn't need -fPIC, and am planning to make
that change sometime.  The reason Makefile.hpux is that way now is that
I was accustomed to needing -fPIC on a different project that generated
shared libraries far bigger than any of ours.

            regards, tom lane

Tom Lane writes:

> I'm not actually convinced that Sparc has a real need for -fPIC, either,
> since Lamar could not reproduce Tom's problem, and the GOT sizes I can
> measure on x86 are an order of magnitude smaller than the Sparc limit.
> I pushed out the change quickly because of the impending 7.3.3 deadline,
> but I'm more than half inclined to revert it.

If we don't have reproduceable evidence then we shouldn't play around with
these things in a minor release.

--
Peter Eisentraut   peter_e@gmx.net

Peter Eisentraut <peter_e@gmx.net> writes:
> Tom Lane writes:
>> I'm not actually convinced that Sparc has a real need for -fPIC, either,
>> since Lamar could not reproduce Tom's problem, and the GOT sizes I can
>> measure on x86 are an order of magnitude smaller than the Sparc limit.
>> I pushed out the change quickly because of the impending 7.3.3 deadline,
>> but I'm more than half inclined to revert it.

> If we don't have reproduceable evidence then we shouldn't play around with
> these things in a minor release.

<shrug> It's not like using -fPIC instead of -fpic could have any worse
consequences than losing a little performance.  And Callaway's word does
carry some weight with me.  I plan to bug him further about what problem
he actually saw before making a decision.

            regards, tom lane