toolchain.eclass: drop GCC_FILESDIR override, bug #629776

GCC_FILESDIR support was broken by portage-2.3.6 commit:
    gentoo/portage@0637c95
("portage.package.ebuild: Use a fake FILESDIR to catch invalid accesses")

Unfortunately it was applied to older EAPIs without fixing all
the users first.

The change yanks GCC_FILESDIR override support and hardcodes
FILESDIR usage (as all the ebuilds except 'gcc' are broken anyway).

Bug: https://bugs.gentoo.org/629776
Signed-off-by: Sergei Trofimovich <[email protected]>

eclass/toolchain.eclass

@@ -90,8 +90,6 @@ if [[ ${SNAPSHOT} == [56789].0-* ]] ; then
 	SNAPSHOT=${SNAPSHOT/.0}
 fi
 
-export GCC_FILESDIR=${GCC_FILESDIR:-${FILESDIR}}
-
 PREFIX=${TOOLCHAIN_PREFIX:-${EPREFIX}/usr}
 
 if tc_version_is_at_least 3.4.0 ; then
@@ -581,14 +579,14 @@ toolchain_src_prepare() {
 	einfo "Fixing misc issues in configure files"
 	for f in $(grep -l 'autoconf version 2.13' $(find "${S}" -name configure)) ; do
 		ebegin "  Updating ${f/${S}\/} [LANG]"
-		patch "${f}" "${GCC_FILESDIR}"/gcc-configure-LANG.patch >& "${T}"/configure-patch.log \
+		patch "${f}" "${FILESDIR}"/gcc-configure-LANG.patch >& "${T}"/configure-patch.log \
 			|| eerror "Please file a bug about this"
 		eend $?
 	done
 	sed -i 's|A-Za-z0-9|[:alnum:]|g' "${S}"/gcc/*.awk #215828
 
 	# Prevent new texinfo from breaking old versions (see #198182, #464008)
-	tc_version_is_at_least 4.1 && epatch "${GCC_FILESDIR}"/gcc-configure-texinfo.patch
+	tc_version_is_at_least 4.1 && epatch "${FILESDIR}"/gcc-configure-texinfo.patch
 
 	if [[ -x contrib/gcc_update ]] ; then
 		einfo "Touching generated files"
@@ -1780,10 +1778,10 @@ toolchain_src_install() {
 	# between binary and source package borks things ....
 	if ! is_crosscompile ; then
 		insinto "${DATAPATH#${EPREFIX}}"
-		newins "$(prefixify_ro "${GCC_FILESDIR}"/awk/fixlafiles.awk-no_gcc_la)" fixlafiles.awk || die
+		newins "$(prefixify_ro "${FILESDIR}"/awk/fixlafiles.awk-no_gcc_la)" fixlafiles.awk || die
 		exeinto "${DATAPATH#${EPREFIX}}"
-		doexe "$(prefixify_ro "${GCC_FILESDIR}"/fix_libtool_files.sh)" || die
-		doexe "${GCC_FILESDIR}"/c{89,99} || die
+		doexe "$(prefixify_ro "${FILESDIR}"/fix_libtool_files.sh)" || die
+		doexe "${FILESDIR}"/c{89,99} || die
 	fi
 
 	# libstdc++.la: Delete as it doesn't add anything useful: g++ itself