it seems we have some cases where eclasses/ebuilds interact poorly.  for
example, if an eclass runs eautoreconf or elibtoolize, and then the ebuild
does some stuff where it ends up running eautoreconf, subsequent elibtoolize
calls are skipped.

this means that the work done by the earlier elibtoolize call was all for
naught, as eautoreconf blows all of its work away be regenerating the files
elibtoolize patched.  and when eautoreconf attempts to run elibtoolize itself,
we don't get all the fun patches since elibtoolize detected it was run
already.

rather than have this continue to silently ignore the issue, i'm thinking of
making these changes:
	- elibtoolize now has a --force flag
	- eautoreconf always calls elibtoolize with --force
	- if elibtoolize detects a previous run with --force, it warns, but runs
this way we complain, but at least we continue to work

the prefix guys first brought this up here:
	https://bugs.gentoo.org/232820
but i've hit this since with cross-compiling Linux targets:
	- pygobject ebuild inherits gnome2 eclass
	- pygobject's src_prepare first calls gnome2_src_prepare
	- gnome2_src_prepare always calls elibtoolize (which normally is good)
	- pygobject's src_prepare applies patches and then calls eautoreconf
	- eautoreconf regens all files that where patched earlier
	- eautoreconf's call to elibtoolize is skipped
	- builds fail which need those elibtoolize patches
-mike

--- autotools.eclass
+++ autotools.eclass
@@ -146,7 +146,7 @@
 
 	# Call it here to prevent failures due to elibtoolize called _before_
 	# eautoreconf.  We set $S because elibtoolize runs on that #265319
-	S=${PWD} elibtoolize
+	S=${PWD} elibtoolize --force
 
 	return 0
 }
--- libtool.eclass
+++ libtool.eclass
@@ -119,6 +119,7 @@
 	local do_uclibc="yes"
 	local deptoremove=
 	local do_shallow="no"
+	local force="false"
 	local elt_patches="install-sh ltmain portage relink max_cmd_len sed test tmp cross as-needed"
 
 	for x in "$@" ; do
@@ -153,6 +154,9 @@
 			--no-uclibc)
 				do_uclibc="no"
 				;;
+			--force)
+				force="true"
+				;;
 			*)
 				eerror "Invalid elibtoolize option: ${x}"
 				die "elibtoolize called with ${x} ??"
@@ -186,9 +190,15 @@
 	for d in "$@" ; do
 		export ELT_APPLIED_PATCHES=
 
-		[[ -f ${d}/.elibtoolized ]] && continue
+		if [[ -f ${d}/.elibtoolized ]] ; then
+			${force} || continue
+		fi
 
 		einfo "Running elibtoolize in: ${d#${WORKDIR}/}/"
+		if [[ -f ${d}/.elibtoolized ]] ; then
+			ewarn "  We've already been run in this tree; you should"
+			ewarn "  avoid this if possible (perhaps by filing a bug)"
+		fi
 
 		for p in ${elt_patches} ; do
 			local ret=0