diff --git a/configure.ac b/configure.ac
index 9c8dfd4d3..8d84a38f0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -16,6 +16,10 @@ AC_CONFIG_AUX_DIR([build-aux])
 : ${CFLAGS=""}
 : ${CXXFLAGS=""}
 
+# Test ar for the "U" option. Should be checked before the libtool macros.
+xxx_ar_flags=$((ar --help) 2>&1)
+AS_CASE([$xxx_ar_flags],[*'use actual timestamps and uids/gids'*],[: ${AR_FLAGS="Ucru"}])
+
 AC_CANONICAL_HOST
 AC_CANONICAL_BUILD