diff --git a/libstdc++-v3/testsuite/26_numerics/complex/proj.cc b/libstdc++-v3/testsuite/26_numerics/complex/proj.cc
index a053119197c..69f8153c06f 100644
--- a/libstdc++-v3/testsuite/26_numerics/complex/proj.cc
+++ b/libstdc++-v3/testsuite/26_numerics/complex/proj.cc
@@ -397,6 +397,19 @@ test03()
 int
 main()
 {
+  /* If neither of these macros is nonzero, proj calls a
+     specialization of the __complex_proj template, that just returns
+     its argument, without testing for infinities, rendering the whole
+     test pointless, and failing (as intended/noted in the
+     implementation) the cases that involve infinities.  Alas, the
+     normal ways to skip tests may not work: we don't have a test for
+     C99_COMPLEX, and these macros may vary depending on -std=*, but
+     macro tests wouldn't take them into account.  */
+#if ! (_GLIBCXX_USE_C99_COMPLEX || _GLIBCXX_USE_C99_MATH_TR1)
+  if (true)
+    return 0;
+#endif
+
   test01();
   test02();
   test03();