app-editors/vim-qt: minor config workaround for building with -flto

This affects all vim packages (braindead configure) but apps build and
run fine with graphite and -flto.

Package-Manager: portage-2.2.24

app-editors/vim-qt/metadata.xml

@@ -3,6 +3,7 @@
 <pkgmetadata>
   <herd>qt</herd>
   <use>
+    <flag name="lto">Enable configure workaround for -flto</flag>
     <flag name="luajit">Use <pkg>dev-lang/luajit</pkg> instead of <pkg>dev-lang/lua</pkg></flag>
     <flag name="racket">Enable support for Scheme using <pkg>dev-lang/racket</pkg></flag>
   </use>

app-editors/vim-qt/vim-qt-20150102-r1.ebuild

@@ -26,7 +26,7 @@ fi
 
 LICENSE="vim"
 SLOT="0"
-IUSE="acl cscope debug lua luajit nls perl python racket ruby"
+IUSE="acl cscope debug lua luajit lto nls perl python racket ruby"
 
 REQUIRED_USE="luajit? ( lua )
 	python? ( ${PYTHON_REQUIRED_USE} )"
@@ -63,6 +63,11 @@ src_prepare() {
 }
 
 src_configure() {
+	if use lto ; then
+		LDFLAGS_OLD="$LDFLAGS"
+		local LDFLAGS="${LDFLAGS} -fno-lto -fno-use-linker-plugin"
+	fi
+
 	use debug && append-flags "-DDEBUG"
 
 	local myconf="--with-features=huge --disable-gpm --enable-multibyte"
@@ -95,6 +100,11 @@ src_configure() {
 	fi
 
 	econf ${myconf} --enable-gui=qt --with-vim-name=qvim --with-modified-by=Gentoo-${PVR}
+
+	if use lto ; then
+		LDFLAGS="${LDFLAGS_OLD}"
+		sed -i -e "s|-fno-lto -fno-use-linker-plugin||g" src/auto/config.mk
+	fi
 }
 
 src_install() {