sched_setaffinity() and sched_getaffinity() implicitly declared

[giampaolo]

From [email protected] on June 29, 2013 09:13:32

sched.h of glibc declares sched_setaffinity() and sched_getaffinity() when 
_GNU_SOURCE is defined. See `man sched_setaffinity`.

When _GNU_SOURCE is not defined anywhere, then compilation might fail:

psutil/_psutil_linux.c: In function ‘get_process_cpu_affinity’:
psutil/_psutil_linux.c:182:5: error: implicit declaration of function 
‘sched_getaffinity’ [-Werror=implicit-function-declaration]
     if (sched_getaffinity(pid, len, (cpu_set_t *)&mask) < 0) {
     ^
psutil/_psutil_linux.c: In function ‘set_process_cpu_affinity’:
psutil/_psutil_linux.c:202:5: error: implicit declaration of function 
‘sched_setaffinity’ [-Werror=implicit-function-declaration]
     if (sched_setaffinity(pid, len, (cpu_set_t *)&mask)) {
     ^

Fix:

--- psutil/_psutil_linux.c
+++ psutil/_psutil_linux.c
@@ -11,6 +11,7 @@
 #include <stdlib.h>
 #include <mntent.h>
 #include <utmp.h>
+#define _GNU_SOURCE
 #include <sched.h>
 #include <sys/syscall.h>
 #include <sys/sysinfo.h>

Original issue: http://code.google.com/p/psutil/issues/detail?id=404

[giampaolo]

From [email protected] on June 30, 2013 00:40:28

Python.h indirectly includes features.h, which has _FEATURES_H check against 
multiple inclusion, so _GNU_SOURCE needs to be defined earlier.

Updated patch:
--- psutil/_psutil_linux.c
+++ psutil/_psutil_linux.c
@@ -6,6 +6,7 @@
  * Linux-specific functions.
  */

+#define _GNU_SOURCE
 #include <Python.h>
 #include <errno.h>
 #include <stdlib.h>

[giampaolo]

From g.rodola on July 04, 2013 07:05:39

Fixed in revision b304cfaf3b7c . Thanks for the patch.

Status: FixedInHG
Labels: OpSys-Linux Milestone-1.0.0

[giampaolo]

From [email protected] on July 04, 2013 07:39:26

First patch was not working. Please move '#define _GNU_SOURCE' before inclusion 
of Python.h.

[giampaolo]

From g.rodola on July 06, 2013 06:02:29

whops! right.
done, thanks.

[giampaolo]

From g.rodola on July 11, 2013 01:54:35

Status: Fixed

[giampaolo]

From g.rodola on August 28, 2013 09:24:42

I'm reopening this as right now we're getting a compiler warning because of 
this change:

/usr/include/python2.7/pyconfig.h:1139:0: warning: "_GNU_SOURCE" redefined 
[enabled by default]

Since I couldn't and still cannot reproduce the original issue, before I commit 
can you please tell me if the following patch breaks anything?


diff --git a/psutil/_psutil_linux.c b/psutil/_psutil_linux.c
--- a/psutil/_psutil_linux.c
+++ b/psutil/_psutil_linux.c
@@ -6,22 +6,26 @@
  * Linux-specific functions.
  */

-#define _GNU_SOURCE
 #include <Python.h>
 #include <errno.h>
 #include <stdlib.h>
 #include <mntent.h>
 #include <utmp.h>
-#include <sched.h>
 #include <sys/syscall.h>
 #include <sys/sysinfo.h>
 #include <sys/time.h>
 #include <sys/resource.h>
 #include <linux/unistd.h>

+// "man sched_setaffinity" dictates to include _GNU_SOURCE but this may
+// be already defined elsewhere
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+#include <sched.h>
+
 #include "_psutil_linux.h"

-
 #define HAS_IOPRIO defined(__NR_ioprio_get) && defined(__NR_ioprio_set)

 #if HAS_IOPRIO

Status: ReOpened

[giampaolo]

From g.rodola on December 02, 2013 11:40:06

Closing this out again as I believe the warning is gone now.

Status: Fixed