diff --git a/m4/libtool.m4 b/m4/libtool.m4
index f2d1f398..4877f31e 100644
--- a/m4/libtool.m4
+++ b/m4/libtool.m4
@@ -5066,7 +5066,7 @@ dnl Note also adjust exclude_expsyms for C++ above.
       _LT_TAGVAR(whole_archive_flag_spec, $1)=
     fi
     supports_anon_versioning=no
-    case `$LD -v | $SED -e 's/([^)]\+)\s\+//' 2>&1` in
+    case `$LD -v | $SED -e 's/([[^)]]\+)\s\+//' 2>&1` in
       *GNU\ gold*) supports_anon_versioning=yes ;;
       *\ [[01]].* | *\ 2.[[0-9]].* | *\ 2.10.*) ;; # catch versions < 2.11
       *\ 2.11.93.0.2\ *) supports_anon_versioning=yes ;; # RH7.3 ...