Bug 90088

	Detectable only I guess, when you install subversion (or it's upstream dependencies)
	before you install apache2.
	Some things to note:
	* CC not set in make.conf
	* cat /usr/local/share/config.site
	# local configure settings

	test x"$CFLAGS" = x"" && CFLAGS='-O2 -fno-strict-aliasing -pipe' # Same as <sys.mk>
	test x"$CC" = x"" && CC='/usr/bin/cc'
	test x"$CXX" = x"" && CXX='/usr/bin/c++'
	test x"$MAKE" = x"" && MAKE='/usr/bin/make'

	* cat /var/db/pkg/apr-nothr-db4-1.2.2_1/+REQUIRED_BY
	c_c++_reference-2.0.2_4
	kde-3.4.3
	kdesdk-3.4.3
	kdevelop-3.2.3
	subversion-1.3.0.r2

	Symptom:
	===>  Building for apache-worker-2.2.0_1
	Making all in srclib
	Making all in pcre
	/usr/local/build-1/libtool --silent --mode=compile cc   -O2 ....
	libtool: compile: unable to infer tagged configuration
	libtool: compile: specify a tag with `--tag'
	*** Error code 1
	
	Analysis:
	$ grep '/cc' /usr/local/build-1/libtool
	LTCC="/usr/bin/cc"
	CC="/usr/bin/cc"
	LTCC="/usr/bin/cc"
	LTCC="/usr/bin/cc"
	
	So, CC is set to <sys.mk>'s default value 'cc' when building apache22,
	while the installed 'tagged' libtool has /usr/bin/cc, which are 'different'
	from libtools point of view.

	The same thing might happen if you set different CC's during either of these
	compiles and it's quite cryptic at first glance.

Fix: 

Several possibilities, my config.site does not conflict with any other port I've
	seen, it's used mainly for my own builds and stuff not in ports, so it leads me
	to believe that the run-autotools target in devel/apr/Makefile should export CC
	and CXX, so that config.site doesn't set it.
	If CC and CXX cannot be exported, add a reference to this PR in pre-configure
	target with the error message described above -;)

	Or: Add a conflict apr-svn <=> apache22.

	As a side note, apr-svn builds without threads, not sure if this is a problem
	if one decides for the worker MPM in apache.
How-To-Repeat: 	Short version:
	pkg_deinstall -f 'apr-*' # if applicable
	portinstall devel/subversion; portinstall www/apache2