[PULL 1/3] linux-user: Guard local FUTEX_CMD_MASK definition

[Helge Deller <deller@kernel.org>]

From: Cédric Le Goater <clg@redhat.com>

Building linux-user on a host with Linux 7.2 kernel headers fails with
a macro redefinition error for FUTEX_CMD_MASK. The kernel commit
3ca9595d9fb6 ("futex: Add support for unlocking robust futexes")
expanded the mask to include the new FUTEX_ROBUST_UNLOCK and
FUTEX_ROBUST_LIST32 flags, which conflicts with QEMU's local
definition.

Add a #ifndef guard so the host definition takes precedence when
available. The local fallback is kept for older kernel headers
(pre-2.6.29) that lack FUTEX_CMD_MASK or define a mask without
FUTEX_CLOCK_REALTIME.

Signed-off-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@oss.qualcomm.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@oss.qualcomm.com>
Signed-off-by: Helge Deller <deller@gmx.de>
---
 linux-user/syscall_defs.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h
index 5799769f83..e033c7db34 100644
--- a/linux-user/syscall_defs.h
+++ b/linux-user/syscall_defs.h
@@ -2593,7 +2593,9 @@ struct target_drm_i915_getparam {
 
 #define FUTEX_PRIVATE_FLAG      128
 #define FUTEX_CLOCK_REALTIME    256
+#ifndef FUTEX_CMD_MASK
 #define FUTEX_CMD_MASK          ~(FUTEX_PRIVATE_FLAG | FUTEX_CLOCK_REALTIME)
+#endif
 
 #if defined(TARGET_X86_64)
 #define TARGET_EPOLL_PACKED QEMU_PACKED
-- 
2.54.0