Work around IA64 tst-setcontext2.c compile failure.

Building tests for IA64 runs into a build failure compiling
stdlib/tst-setcontext2.c:

tst-setcontext2.c: In function 'do_test':
tst-setcontext2.c:210:20: error: passing argument 1 of 'sigismember' from incompatible pointer type [-Werror=incompatible-pointer-types]
   if (sigismember (&oldctx.uc_sigmask, SIGUSR2) != 1)
                    ^

Indeed, the IA64 uc_sigmask as unsigned long rather than the larger
userspace sigset_t.  Fixing this might be hard; this patch works
around the build failure by making IA64 wrap the test with a version
that #defines sigismember to add a cast (I'd welcome a better approach
for fixing this).

Tested (compilation only) for ia64.

	* sysdeps/unix/sysv/linux/ia64/tst-setcontext2.c: New file.

2 files changed, 26 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index 6d9b162..591b4c0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,7 @@
 2016-11-28  Joseph Myers  <joseph@codesourcery.com>
 
+	* sysdeps/unix/sysv/linux/ia64/tst-setcontext2.c: New file.
+
 	* sysdeps/ia64/fpu/libm-symbols.h: Make contents conditional on
 	[!__STRICT_ANSI__ && !__cplusplus].
 
diff --git a/sysdeps/unix/sysv/linux/ia64/tst-setcontext2.c b/sysdeps/unix/sysv/linux/ia64/tst-setcontext2.c
new file mode 100644
index 0000000..7adc059
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/ia64/tst-setcontext2.c
@@ -0,0 +1,24 @@
+/* Work around incorrect type of IA64 uc_sigmask.
+   Copyright (C) 2016 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 <signal.h>
+
+#undef sigismember
+#define sigismember(set, signo) sigismember ((const sigset_t *) (set), (signo))
+
+#include <stdlib/tst-setcontext2.c>