From: Kees Cook <keescook@xxxxxxxxxxxx> Subject: samples/vfs: avoid warning in statx override Something changed recently to uncover this warning: samples/vfs/test-statx.c:24:15: warning: `struct foo' declared inside parameter list will not be visible outside of this definition or declaration 24 | #define statx foo | ^~~ Which is due the use of "struct statx" (here, "struct foo") in a function prototype argument list before it has been defined: int # 56 "/usr/include/x86_64-linux-gnu/bits/statx-generic.h" foo # 56 "/usr/include/x86_64-linux-gnu/bits/statx-generic.h" 3 4 (int __dirfd, const char *__restrict __path, int __flags, unsigned int __mask, struct # 57 "/usr/include/x86_64-linux-gnu/bits/statx-generic.h" foo # 57 "/usr/include/x86_64-linux-gnu/bits/statx-generic.h" 3 4 *__restrict __buf) __attribute__ ((__nothrow__ , __leaf__)) __attribute__ ((__nonnull__ (2, 5))); Add explicit struct before #include to avoid warning. Link: http://lkml.kernel.org/r/202006282213.C516EA6@keescook Fixes: f1b5618e013a ("vfs: Add a sample program for the new mount API") Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> Cc: Miklos Szeredi <mszeredi@xxxxxxxxxx> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: David Howells <dhowells@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- samples/vfs/test-statx.c | 2 ++ 1 file changed, 2 insertions(+) --- a/samples/vfs/test-statx.c~samples-vfs-avoid-warning-in-statx-override +++ a/samples/vfs/test-statx.c @@ -23,6 +23,8 @@ #include <linux/fcntl.h> #define statx foo #define statx_timestamp foo_timestamp +struct statx; +struct statx_timestamp; #include <sys/stat.h> #undef statx #undef statx_timestamp _