[PATCH] openat-die: use _Noreturn markup

[Eric Blake]

Compiling coreutils.git on cygwin with gcc 4.8.3, I got:

lib/openat-die.c:34:1: error: function might be candidate for attribute 
'noreturn' [-Werror=suggest-attribute=noreturn]
 openat_save_fail (int errnum)
 ^

* modules/openat-die (Depends-on): Add stdnoreturn.
* lib/openat-die.c (openat_save_fail, openat_restore_fail): Mark
_Noreturn.

Signed-off-by: Eric Blake <address@hidden>
---

I noticed that the c-stack module does NOT depend on the stdnoreturn
modules, and that lib/c-stack.c does not include <stdnoreturn.h> but
DOES use _Noreturn.  Therefore, I'm not 100% sure that this patch is
right, and if we need to touch up other modules that are using
_Noreturn improperly; vs. this patch being too complex and I could
just simplify it to be more like c-stack.c.  I _think_ c-stack.c was
getting a guaranteed _Noreturn by virtue of (indirectly) getting
a definition from the stdlib module using snippet/_Noreturn.

 ChangeLog          | 7 +++++++
 lib/openat-die.c   | 5 +++--
 modules/openat-die | 1 +
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 73a6c03..62025f2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2014-07-30  Eric Blake  <address@hidden>
+
+       openat-die: use _Noreturn markup
+       * modules/openat-die (Depends-on): Add stdnoreturn.
+       * lib/openat-die.c (openat_save_fail, openat_restore_fail): Mark
+       _Noreturn.
+
 2014-07-19  Eli Zaretskii  <address@hidden>

        localename: Enforce declarations before statements.
diff --git a/lib/openat-die.c b/lib/openat-die.c
index 02f1fd7..cfd65af 100644
--- a/lib/openat-die.c
+++ b/lib/openat-die.c
@@ -20,6 +20,7 @@
 #include "openat.h"

 #include <stdlib.h>
+#include <stdnoreturn.h>

 #ifndef GNULIB_LIBPOSIX
 # include "error.h"
@@ -30,7 +31,7 @@
 #include "gettext.h"
 #define _(msgid) gettext (msgid)

-void
+void _Noreturn
 openat_save_fail (int errnum)
 {
 #ifndef GNULIB_LIBPOSIX
@@ -49,7 +50,7 @@ openat_save_fail (int errnum)
    during an openat emulation.  The caller must ensure that fd 2 is
    not a just-opened fd, even when openat_safer is not in use.  */

-void
+void _Noreturn
 openat_restore_fail (int errnum)
 {
 #ifndef GNULIB_LIBPOSIX
diff --git a/modules/openat-die b/modules/openat-die
index 08bef77..c215f56 100644
--- a/modules/openat-die
+++ b/modules/openat-die
@@ -9,6 +9,7 @@ openat-h
 error
 exitfail
 gettext-h
+stdnoreturn

 configure.ac:

-- 
1.9.3