Subject: Re: More on shared objects problem
To: Todd Vierling <tv@pobox.com>
From: D'Arcy" "J.M. <darcy@druid.druid.net>
List: current-users
Date: 07/27/1999 13:08:56
Thus spake Todd Vierling
> On Tue, 27 Jul 1999, D'Arcy J.M. Cain wrote:
> :     ld -shared -L${PGDIR}/lib --export-dynamic -rpath ${PGDIR}/lib \
> :             -lpq -lc -o $@ $<
> 
> --export-dynamic is only needed for _executables_.  It is implied for shared
> objects.

So I have been told.  Removing it didn't help though.

> BTW, for platform compatibility, may I suggest using -R instead of -rpath...
> that works on all NetBSD, a.out and ELF, linkers (and even some non-NetBSD
> ones :).

OK, I did that.

> ...and you don't have --export-dynamic on your _executable's_ link line.
> When linking the executable whose symbols will be used by a shared object,
> use:
> 
> cc -Wl,-E ...

Hmm.  OK, I'll try to get that into the PostgreSQL code.  Is that flag
benign on a non-ELF system or do I have to test for ELF before adding
the flag?

> You need the sources of src/gnu/lib/libbfd and
> src/gnu/dist/{opcodes,bfd,libiberty} in order to build any libbfd using
> program.  This is because there are a lot of internal bfd headers used by
> these programs.  However, there is nothing wrong with your nm.

I just realized that I have not been supping gnu files.  Didn't someone
say here that src/gnu was now included in /src?  I supped the current
gnu down and will rebuild the world but I will try the -E first.

Bingo!  That was it.  OK, I'll see that the change gets back into PostgreSQL.
Hmmm.  Looking at the code I see that it does expect to add that flag if
it is on an ELF system.  I guess configure needs to be tweaked.  I'll
copy (and set followups to) the PostgreSQL list to start discussions
there on that.

So how do we determine that a system is elf?  I don't see it in uname.  Do
we just run file(1) on the kernel and see if the string "ELF" shows up?

Many thanks for everyone's help.

-- 
D'Arcy J.M. Cain <darcy@{druid|vex}.net>   |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 424 2871     (DoD#0082)    (eNTP)   |  what's for dinner.