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Date: Tue, 1 Apr 2003 11:40:52 -0800
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Subject: exports.c dependencies
From: "Roy T. Fielding" <fielding@apache.org>
To: dev@apr.apache.org
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Message-Id: <D92DB48A-6479-11D7-AE5B-000393753936@apache.org>

I have been trying to fix a simple warning in httpd 2.1 and am getting
stuck in spaghetti.  apr_sendfile is being exported even when it is not
usable, and as a result there is no declaration prior to implementation
of the function in network_io.  So, I fix that and find that it won't
build because exports.c is being created dynamically by the Makefile
but using some odd combination of files to check dependencies rather
than make itself.  I find the make target for delete-exports, but note
that it isn't implemented recursively like our normal targets and thus
can't be run from the top.  Then I notice that exports is not cleaned
by a distclean, but rather by extraclean, which means we ship exports
as it was found on the RM's machine rather than the user's machine,
and the funky logic in the Makefile appears to specifically avoid
recreating it.  WTF?  Mind you, exports isn't even needed if you don't
compile shared, so this whole thing is a waste of time for people
who compile static.

Can somebody please explain what they are trying to accomplish with
exports and why it isn't being created by configure?  My guess is that
someone is attempting to create a single shared library that will
work on a platform where sendfile may or may not be avaiable.  If so,
then please fix the problem and not the side-effect: remove the
APR_HAS_SENDFILE conditionals from all of the exported declarations
so that it is always exported.  We can then simplify the creation
of exports.c.

....Roy