fixed lto for newer gcc

debian/rules

@@ -13,13 +13,17 @@ DPKG_EXPORT_BUILDFLAGS = 1
 export DEB_BUILD_MAINT_OPTIONS=hardening=+all
 
 GRAPHITE = -floop-interchange -ftree-loop-distribution -floop-strip-mine -floop-block -ftree-vectorize
-LTO = -flto -fuse-linker-plugin -flto-compression-level=9 -flto-partition=1to1
+LTO = -flto -fuse-linker-plugin -flto-compression-level=9 -flto-partition=1to1 -fuse-ld=gold
 
 DEB_CPPFLAGS_MAINT_APPEND := -DNDEBUG
 DEB_CFLAGS_MAINT_APPEND := -fomit-frame-pointer $(GRAPHITE) $(LTO)
 DEB_CXXFLAGS_MAINT_APPEND := -fomit-frame-pointer $(GRAPHITE) $(LTO)
 DEB_LDFLAGS_MAINT_APPEND := $(CXXFLAGS) $(GRAPHITE) $(LTO)
 
+export NM=gcc-nm
+export AR=gcc-ar
+export RANLIB=gcc-ranlib
+
 include /usr/share/cdbs/1/rules/debhelper.mk
 include /usr/share/cdbs/1/class/autotools.mk
 include /usr/share/cdbs/1/rules/autoreconf.mk