[src/trunk]: src/tests/lib/libm Add a short case for the alpha test failure

[maya <maya%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/026d678b6bb9
branches:  trunk
changeset: 826377:026d678b6bb9
user:      maya <maya%NetBSD.org@localhost>
date:      Wed Aug 30 22:55:41 2017 +0000

description:
Add a short case for the alpha test failure

Now I see it's down to the choice of -mfp-trap-mode (n works, su/sui/u don't)

diffstat:

 tests/lib/libm/t_round.c |  19 ++++++++++++++++++-
 1 files changed, 18 insertions(+), 1 deletions(-)

diffs (45 lines):

diff -r e13feae86f05 -r 026d678b6bb9 tests/lib/libm/t_round.c
--- a/tests/lib/libm/t_round.c  Wed Aug 30 16:01:55 2017 +0000
+++ b/tests/lib/libm/t_round.c  Wed Aug 30 22:55:41 2017 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: t_round.c,v 1.6 2017/08/30 14:24:20 maya Exp $ */
+/* $NetBSD: t_round.c,v 1.7 2017/08/30 22:55:41 maya Exp $ */
 
 /*-
  * Copyright (c) 2011 The NetBSD Foundation, Inc.
@@ -32,6 +32,7 @@
 #include <float.h>
 #include <math.h>
 #include <stdio.h>
+#include <stdint.h>
 
 /*
  * This tests for a bug in the initial implementation where
@@ -108,11 +109,27 @@
         }
 }
 
+ATF_TC(rounding_alpha_simple);
+ATF_TC_HEAD(rounding_alpha_simple, tc)
+{
+       atf_tc_set_md_var(tc, "descr","Checking double to uint64_t edge case");
+}
+
+ATF_TC_BODY(rounding_alpha_simple, tc)
+{
+       double even = 9223372036854775808.000000; /* 2^63 */
+       uint64_t unsigned_even = even;
+
+       ATF_CHECK_MSG(unsigned_even % 2 == 0,
+           "2^63 casted to uint64_t is odd");
+
+}
 ATF_TP_ADD_TCS(tp)
 {
 
        ATF_TP_ADD_TC(tp, round_dir);
        ATF_TP_ADD_TC(tp, rounding_alpha);
+       ATF_TP_ADD_TC(tp, rounding_alpha_simple);
 
        return atf_no_error();
 }