Fix strtod handling of underflow (bug 14047).

1 files changed, 69 insertions, 0 deletions

diff --git a/stdlib/tst-tininess.c b/stdlib/tst-tininess.c
new file mode 100644
index 0000000..9312f16
--- /dev/null
+++ b/stdlib/tst-tininess.c
@@ -0,0 +1,69 @@
+/* Test that tininess.h is correct for this architecture.
+   Copyright (C) 2012 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fenv.h>
+#include <float.h>
+#include <stdio.h>
+#include <tininess.h>
+
+volatile float a = 0x1.fffp-126;
+volatile float b = 0x1.0008p-1;
+volatile float c;
+volatile float m = FLT_MIN;
+volatile float mm;
+
+static int
+do_test (void)
+{
+  int result = 0;
+#ifdef FE_UNDERFLOW
+  feclearexcept (FE_ALL_EXCEPT);
+  mm = m * m;
+  if (!fetestexcept (FE_UNDERFLOW))
+    {
+      puts ("underflow exception not supported at runtime, cannot test");
+      return 0;
+    }
+  feclearexcept (FE_ALL_EXCEPT);
+  c = a * b;
+  if (fetestexcept (FE_UNDERFLOW))
+    {
+      if (TININESS_AFTER_ROUNDING)
+	{
+	  puts ("tininess.h says after rounding, "
+		"but detected before rounding");
+	  result = 1;
+	}
+    }
+  else
+    {
+      if (!TININESS_AFTER_ROUNDING)
+	{
+	  puts ("tininess.h says before rounding, "
+		"but detected after rounding");
+	  result = 1;
+	}
+    }
+#else
+  puts ("underflow exception not supported at compile time, cannot test");
+#endif
+  return result;
+}
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"