From 48273d42bc0689d6e8e79c1750a62f6bc3721307 Mon Sep 17 00:00:00 2001
From: Joseph Myers <joseph@codesourcery.com>
Date: Fri, 23 Jun 2017 20:10:45 +0000
Subject: [PATCH] Make libm-test-support code clear exceptions after each test.

The libm-test-support code clears exceptions at the end of
test_exceptions.  However, it's possible that exceptions get raised as
part of the subsequent checks on the results of the function being
tested, and such exceptions then carry through to the next test run
and can cause that to fail spuriously.  In particular, it's possible
for the ulps calculation to raise exceptions in some cases.  This
patch puts exception clearing at the end of each of the check_*
functions, alongside errno clearing, to avoid one test affecting the
next in that way.

Tested for x86_64 (in conjunction with float128 patches).

	* libm-test-support.c (check_float_internal): Clear exceptions at
	end of function.
	(check_int): Likewise.
	(check_long): Likewise.
	(check_bool): Likewise.
	(check_longlong): Likewise.
	(check_intmax_t): Likewise.
	(check_uintmax_t): Likewise.
---
 ChangeLog                | 9 +++++++++
 math/libm-test-support.c | 7 +++++++
 2 files changed, 16 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index fa0ac20c19..464e65d101 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,14 @@
 2017-06-23  Joseph Myers  <joseph@codesourcery.com>
 
+	* libm-test-support.c (check_float_internal): Clear exceptions at
+	end of function.
+	(check_int): Likewise.
+	(check_long): Likewise.
+	(check_bool): Likewise.
+	(check_longlong): Likewise.
+	(check_intmax_t): Likewise.
+	(check_uintmax_t): Likewise.
+
 	* sysdeps/x86/fpu/bits/fenv.h [_LIBC] (__feraiseexcept_renamed):
 	Do not declare.
 	* sysdeps/x86/fpu/include/bits/fenv.h [_LIBC &&
diff --git a/math/libm-test-support.c b/math/libm-test-support.c
index 7612d394d6..078d30743d 100644
--- a/math/libm-test-support.c
+++ b/math/libm-test-support.c
@@ -718,6 +718,7 @@ check_float_internal (const char *test_name, FLOAT computed, FLOAT expected,
 
  out:
   fpstack_test (test_name);
+  feclearexcept (FE_ALL_EXCEPT);
   errno = 0;
 }
 
@@ -795,6 +796,7 @@ check_int (const char *test_name, int computed, int expected,
   update_stats (ok);
  out:
   fpstack_test (test_name);
+  feclearexcept (FE_ALL_EXCEPT);
   errno = 0;
 }
 
@@ -828,6 +830,7 @@ check_long (const char *test_name, long int computed, long int expected,
   update_stats (ok);
  out:
   fpstack_test (test_name);
+  feclearexcept (FE_ALL_EXCEPT);
   errno = 0;
 }
 
@@ -861,6 +864,7 @@ check_bool (const char *test_name, int computed, int expected,
   update_stats (ok);
  out:
   fpstack_test (test_name);
+  feclearexcept (FE_ALL_EXCEPT);
   errno = 0;
 }
 
@@ -895,6 +899,7 @@ check_longlong (const char *test_name, long long int computed,
   update_stats (ok);
  out:
   fpstack_test (test_name);
+  feclearexcept (FE_ALL_EXCEPT);
   errno = 0;
 }
 
@@ -928,6 +933,7 @@ check_intmax_t (const char *test_name, intmax_t computed,
   update_stats (ok);
  out:
   fpstack_test (test_name);
+  feclearexcept (FE_ALL_EXCEPT);
   errno = 0;
 }
 
@@ -961,6 +967,7 @@ check_uintmax_t (const char *test_name, uintmax_t computed,
   update_stats (ok);
  out:
   fpstack_test (test_name);
+  feclearexcept (FE_ALL_EXCEPT);
   errno = 0;
 }
 
-- 
2.11.4.GIT