linux-yocto/samples
Linus Torvalds a48f822908 samples: work around glibc redefining some of our defines wrong
Apparently as of version 2.42, glibc headers define AT_RENAME_NOREPLACE
and some of the other flags for renameat2() and friends in <stdio.h>.

Which would all be fine, except for inexplicable reasons glibc decided
to define them _differently_ from the kernel definitions, which then
makes some of our sample code that includes both kernel headers and user
space headers unhappy, because the compiler will (correctly) complain
about redefining things.

Now, mixing kernel headers and user space headers is always a somewhat
iffy proposition due to namespacing issues, but it's kind of inevitable
in our sample and selftest code.  And this is just glibc being stupid.

Those defines come from the kernel, glibc is exposing the kernel
interfaces, and glibc shouldn't make up some random new expressions for
these values.

It's not like glibc headers changed the actual result values, but they
arbitrarily just decided to use a different expression to describe those
values.  The kernel just does

    #define AT_RENAME_NOREPLACE  0x0001

while glibc does

    # define RENAME_NOREPLACE (1 << 0)
    # define AT_RENAME_NOREPLACE RENAME_NOREPLACE

instead.  Same value in the end, but very different macro definition.

For absolutely no reason.

This has since been fixed in the glibc development tree, so eventually
we'll end up with the canonical expressions and no clashes.  But in the
meantime the broken headers are in the glibc-2.42 release and have made
it out into distributions.

Do a minimal work-around to make the samples build cleanly by just
undefining the affected macros in between the user space header include
and the kernel header includes.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2025-11-21 09:29:02 -08:00
..
acrn virt: acrn: Fix typos 2024-05-04 18:59:44 +02:00
auxdisplay
binderfs
bpf
cgroup samples/cgroup: rm unused MEMCG_EVENTS macro 2025-09-21 14:22:26 -07:00
check-exec
configfs
connector
coresight
damon samples/damon/mtier: use damon_initialized() 2025-09-21 14:22:39 -07:00
fanotify samples: fix building fs-monitor on musl systems 2025-07-28 18:14:15 +02:00
fprobe
ftrace ftrace/samples: Fix function size computation 2025-09-05 18:39:12 -04:00
hid
hidraw
hung_task samples: enhance hung_task detector test with read-write semaphore support 2025-07-19 19:08:26 -07:00
hw_breakpoint
kdb
kfifo
kmemleak
kobject
kprobes
landlock
livepatch
mei
nitro_enclaves
pfsm
pidfd
pktgen
qmi
rpmsg
rust Char/Misc/IIO/Binder changes for 6.18-rc1 2025-10-04 16:26:32 -07:00
seccomp
timers
trace_events
trace_printk
tsm-mr
uhid
user_events
v4l media: v4l2-pci-skeleton: Rename second ioctl handlers argument to 'void *priv' 2025-08-13 08:33:59 +02:00
vfio-mdev
vfs samples: work around glibc redefining some of our defines wrong 2025-11-21 09:29:02 -08:00
watch_queue samples: work around glibc redefining some of our defines wrong 2025-11-21 09:29:02 -08:00
watchdog
Kconfig samples: Kconfig: fix spelling mistake "instancess" -> "instances" 2025-08-02 12:01:41 -07:00
Makefile