diff --git a/glib/tests/regex.c b/glib/tests/regex.c
index 833e5850c..b886b0618 100644
--- a/glib/tests/regex.c
+++ b/glib/tests/regex.c
@@ -2628,8 +2628,11 @@ main (int argc, char *argv[])
   TEST_EXPAND("a", "a", "\\0130", FALSE, "X");
   TEST_EXPAND("a", "a", "\\\\\\0", FALSE, "\\a");
   TEST_EXPAND("a(?P<G>.)c", "xabcy", "X\\g<G>X", FALSE, "XbX");
+#ifndef USE_SYSTEM_PCRE
+  /* PCRE >= 8.34 no longer allows this usage. */
   TEST_EXPAND("(.)(?P<1>.)", "ab", "\\1", FALSE, "a");
   TEST_EXPAND("(.)(?P<1>.)", "ab", "\\g<1>", FALSE, "a");
+#endif
   TEST_EXPAND(".", EURO, "\\0", FALSE, EURO);
   TEST_EXPAND("(.)", EURO, "\\1", FALSE, EURO);
   TEST_EXPAND("(?P<G>.)", EURO, "\\g<G>", FALSE, EURO);