conditional DSO support? (was: Re: alpha4)

[Greg Stein <gs...@lyra.org>]

On Mon, 5 Jun 2000 rbb@covalent.net wrote:
>...
> > I still don't see what point of disabling DSO support is. Why not just
> > always include it if it's supported on the build platform? That would make
> > the problem & complexity go away.
> 
> Because people don't like that.  Turning on DSO support requires that we
> add -ldl to the LIBS variable for ALL builds.  This has been vetoed
> already.

I think you may have misunderstood my issue.

-ldl is appropriate for DSO support on *SOME* platforms. APR was including
it unconditionally on ALL platforms, which is incorrect.

APR should just include DSO support, all the time, presuming it is
available on the target platform. This whole "optional this or that"
introduces complexity, uncertainty, and all for little benefit.

Seriously... WHY should we drop out the DSO support when it is available?

>...
> > The only part of APR I can see a point in disabling is threads because
> > thread safeness can incur an expense (mutex locks etc). It's fairly common
> > for run time libraries to come in single & multi threaded versions.
> 
> We want to be able to turn things on and off in APR because of the size of
> the APR binary.

If APR is built as a .so, then this is a pretty moot issue. If APR is
built as a plain .a, then the linker will only pull in necessary pieces.


Case in point: look at the thread this spawned. All kinds of discussion
about how to do partial building, separate or combined .a files, mother
.DLLs or a bunch of little ones, configuration complexities, etc.

Let's simplify!

Cheers,
-g

-- 
Greg Stein, http://www.lyra.org/

Re: conditional DSO support? (was: Re: alpha4)

[Greg Stein <gs...@lyra.org>]

On Mon, 5 Jun 2000 rbb@covalent.net wrote:
>...
> Would you mind telling me how you are planning on having APR tell Apache
> if a Library is needed for the build?

The need for APR to tell Apache about required headers is a generic
problem, and has nothing to do with the DSO issue specifically.

For that matter, how does APR tell Apache to include -lpth? On Solaris,
how does it say to use -lsocket? How about -ltruerand?

Do I have an answer? No. Didn't know that I was supposed to have one :-)
I'd imagine that APR can construct a file that specifies the libraries,
and Apache can do "link ... `src/lib/apr/libraries-needed`" or something.

Cheers,
-g

-- 
Greg Stein, http://www.lyra.org/

Re: conditional DSO support? (was: Re: alpha4)

[rb...@covalent.net]

> > > I still don't see what point of disabling DSO support is. Why not just
> > > always include it if it's supported on the build platform? That would make
> > > the problem & complexity go away.
> > 
> > Because people don't like that.  Turning on DSO support requires that we
> > add -ldl to the LIBS variable for ALL builds.  This has been vetoed
> > already.
> 
> I think you may have misunderstood my issue.
> 
> -ldl is appropriate for DSO support on *SOME* platforms. APR was including
> it unconditionally on ALL platforms, which is incorrect.

First of all, APR wasn't and isn't doing ANYTHING with -ldl, except using
it where available.  Apache is pulling in -ldl unconditionally, which is 
wrong.

Would you mind telling me how you are planning on having APR tell Apache
if a Library is needed for the build?

> APR should just include DSO support, all the time, presuming it is
> available on the target platform. This whole "optional this or that"
> introduces complexity, uncertainty, and all for little benefit.
> 
> Seriously... WHY should we drop out the DSO support when it is available?

I'll take out that option now.

Ryan~

_______________________________________________________________________________
Ryan Bloom                        	rbb@apache.org
406 29th St.
San Francisco, CA 94131
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