Re: [PATCH] uapi/fcntl: conditionally define AT_RENAME* macros

[Matthew Wilcox <willy@infradead.org>]

On Sun, Aug 24, 2025 at 03:10:55PM -0700, Randy Dunlap wrote:
> Don't define the AT_RENAME_* macros when __USE_GNU is defined since
> /usr/include/stdio.h defines them in that case (i.e. when _GNU_SOURCE
> is defined, which causes __USE_GNU to be defined).
> 
> Having them defined in 2 places causes build warnings (duplicate
> definitions) in both samples/watch_queue/watch_test.c and
> samples/vfs/test-statx.c.

It does?  What flags?

#define AT_RENAME_NOREPLACE     0x0001
#define AT_RENAME_NOREPLACE     0x0001

int main(void)
{
	return AT_RENAME_NOREPLACE;
}

gcc -W -Wall testA.c -o testA

(no warnings)

I'm pretty sure C says that duplicate definitions are fine as long
as they're identical.