1 files changed, 24 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.c-torture/execute/ieee/mzero6.c b/gcc/testsuite/gcc.c-torture/execute/ieee/mzero6.c
new file mode 100644
index 000000000..59ba6fee1
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/ieee/mzero6.c
@@ -0,0 +1,24 @@
+/* Tail call optimizations would convert func() into the moral equivalent of:
+
+       double acc = 0.0;
+       for (int i = 0; i <= n; i++)
+	 acc += d;
+       return acc;
+
+   which mishandles the case where 'd' is -0.  They also initialised 'acc'
+   to a zero int rather than a zero double.  */
+
+double func (double d, int n)
+{
+  if (n == 0)
+    return d;
+  else
+    return d + func (d, n - 1);
+}
+
+int main ()
+{
+  if (__builtin_copysign (1.0, func (0.0 / -5.0, 10)) != -1.0)
+    abort ();
+  exit (0);
+}