[RFC PATCH] samples/landlock: Fix building on musl libc

[Brahmajit Das]

Building with make allyesconfig on musl results in the following

In file included from samples/landlock/sandboxer.c:22:
/usr/include/sys/prctl.h:88:8: error: redefinition of 'struct prctl_mm_map'
   88 | struct prctl_mm_map {
      |        ^~~~~~~~~~~~
In file included from samples/landlock/sandboxer.c:16:
usr/include/linux/prctl.h:134:8: note: originally defined here
  134 | struct prctl_mm_map {
      |        ^~~~~~~~~~~~

This is mainly due to differnece in the sys/prctl.h between glibC and
musl. The struct prctl_mm_map is defined in sys/prctl.h in musl.

Signed-off-by: Brahmajit Das <listout at listout.xyz>
---
 samples/landlock/sandboxer.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/samples/landlock/sandboxer.c b/samples/landlock/sandboxer.c
index 4e2854c6f9a3..3cc990618f5b 100644
--- a/samples/landlock/sandboxer.c
+++ b/samples/landlock/sandboxer.c
@@ -13,7 +13,9 @@
 #include <errno.h>
 #include <fcntl.h>
 #include <linux/landlock.h>
+#if defined(__GLIBC__)
 #include <linux/prctl.h>
+#endif
 #include <linux/socket.h>
 #include <stddef.h>
 #include <stdio.h>
-- 
2.50.0