diff --git a/libgrust/configure b/libgrust/configure
index 5388a0e22a6..e778a253915 100755
--- a/libgrust/configure
+++ b/libgrust/configure
@@ -2387,7 +2387,8 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu
 ac_config_files="$ac_config_files Makefile"
 
 
-# Default to --enable-multilib
+if test -n "${with_target_subdir}"; then
+  # Default to --enable-multilib
 # Check whether --enable-multilib was given.
 if test "${enable_multilib+set}" = set; then :
   enableval=$enable_multilib; case "$enableval" in
@@ -2424,6 +2425,7 @@ fi
 
 ac_config_commands="$ac_config_commands default-1"
 
+fi
 
 # Do not delete or change the following two lines.  For why, see
 # http://gcc.gnu.org/ml/libstdc++/2003-07/msg00451.html
@@ -12653,7 +12655,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 12656 "configure"
+#line 12658 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -12759,7 +12761,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 12762 "configure"
+#line 12764 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
diff --git a/libgrust/configure.ac b/libgrust/configure.ac
index 226c42ba649..adfb3500fb3 100644
--- a/libgrust/configure.ac
+++ b/libgrust/configure.ac
@@ -2,7 +2,9 @@ AC_INIT([libgrust], version-unused,,libgrust)
 AC_CONFIG_SRCDIR(Makefile.am)
 AC_CONFIG_FILES([Makefile])
 
-AM_ENABLE_MULTILIB(, ..)
+if test -n "${with_target_subdir}"; then
+  AM_ENABLE_MULTILIB(, ..)
+fi
 
 # Do not delete or change the following two lines.  For why, see
 # http://gcc.gnu.org/ml/libstdc++/2003-07/msg00451.html