pay attention to the multilib support in gcc and move also libs in subdir(s). This is mainly important under Solaris where 32 and 64 bit versions of libs are build and installed

gcc/gcc.spec

@@ -196,6 +196,13 @@ Provides:     gcc = %{version}-%{release}
     #   cleanup installation tree
     mv $RPM_BUILD_ROOT%{l_prefix}/lib/lib*.a \
        $RPM_BUILD_ROOT%{l_prefix}/lib/gcc%{V_comp}-lib/${triple}/%{V_full}/
+    for multilib in `$RPM_BUILD_ROOT%{l_prefix}/bin/gcc --print-multi-lib`; do
+        subdir=`echo "$multilib" | sed -e 's/;.*$//'`
+        [ ".$subdir" = .. ] && continue
+        mv $RPM_BUILD_ROOT%{l_prefix}/lib/$subdir/lib*.a \
+           $RPM_BUILD_ROOT%{l_prefix}/lib/gcc%{V_comp}-lib/${triple}/%{V_full}/$subdir/
+        rm -rf $RPM_BUILD_ROOT%{l_prefix}/lib/$subdir
+    done
     mv $RPM_BUILD_ROOT%{l_prefix}/${triple}/include/* \
        $RPM_BUILD_ROOT%{l_prefix}/lib/gcc%{V_comp}-lib/${triple}/%{V_full}/include/ \
            >/dev/null 2>&1 || true