Re: [HACKERS] Bad libraries again in latest snapshot , libpgtcl and pltcl

Constantin Teodorescu <teo@flex.ro> writes:
> Compiled on my RedHat 5.2 i386 Pentium machine, kernel 2.0.36 with
> ./configure --with-tcl
> I has compiled ok but the same errors occured :
> * for libpgtcl I have to add manually -lcrypt to SHLIBS in Makefile
> * for pltcl I have to add manually -lc

OK, the pltcl problem is easily fixed --- closer inspection of Tcl's
makefiles shows that we weren't using the results read from tclConfig.sh
properly.

The other problem turns out to be even nastier than I feared.  It seems
that on some Unix platforms (evidently including teo's Linux version),
the link command that builds a shared library *must* mention any other
shared libraries that that lib depends on.

On other Unix platforms, not only is it not necessary to mention
shared-lib dependencies, but it may actually Not Work.

I find this information in the configure.in file for Tcl, which is
probably a fairly reliable source since Tcl/Tk has the same problem
we do of one shlib depending on another.

(Curiously, Tcl believes that on Linux dependent shlibs should *not* be
mentioned.  This leads me to think that there is something unusual or
broken about teo's system.  I don't know what, though.)

At this point I have no way to know whether adding -lcrypt to the link
command for libpgtcl.so would break things on more systems than it
fixes ... and so I am not about to just check in that change.

We could try making it system-dependent, using the info in Tcl's
configure file as a guide, but that doesn't strike me as something
I want to try to stick in just a few days before 6.4.1 release either.

The more I learn about this stuff, the more I think that we should get
out of the business of writing our own shlib build/install rules and
let libtool do the work instead.
        regards, tom lane