getgroups: Avoid invoking test with wrong parameters.

[gnulib.git] / tests / test-isnanl.h

diff --git a/tests/test-isnanl.h b/tests/test-isnanl.h
index d897190..8567f39 100644 (file)
--- a/tests/test-isnanl.h
+++ b/tests/test-isnanl.h
@@ -33,9 +33,15 @@
     }                                                                       \
   while (0)
 
-/* HP cc on HP-UX 10.20 has a bug with the constant expression -0.0L.
-   So we use -zero instead.  */
-long double zero = 0.0L;
+/* On HP-UX 10.20, negating 0.0L does not yield -0.0L.
+   So we use minus_zero instead.
+   Note that the expression -LDBL_MIN * LDBL_MIN does not work on other
+   platforms, such as when cross-compiling to PowerPC on MacOS X 10.5.  */
+#if defined __hpux || defined __sgi
+long double minus_zero = -LDBL_MIN * LDBL_MIN;
+#else
+long double minus_zero = -0.0L;
+#endif
 
 int
 main ()
@@ -53,7 +59,7 @@ main ()
   ASSERT (!isnanl (-2.718e30L));
   ASSERT (!isnanl (-2.718e-30L));
   ASSERT (!isnanl (0.0L));
-  ASSERT (!isnanl (-zero));
+  ASSERT (!isnanl (minus_zero));
   /* Infinite values.  */
   ASSERT (!isnanl (1.0L / 0.0L));
   ASSERT (!isnanl (-1.0L / 0.0L));