From: Jason Xing <kernelxing@xxxxxxxxxxx> In some environments (gcc treated as error in W=1, which is default), if we make -C samples/bpf/, it will be stopped because of "no previous prototype" error like this: ../samples/bpf/syscall_nrs.c:7:6: error: no previous prototype for ‘syscall_defines’ [-Werror=missing-prototypes] void syscall_defines(void) ^~~~~~~~~~~~~~~ Actually, this file meets our expectatations because it will be converted to a .h file. In this way, it's correct. Considering the warnning stopping us compiling, we can remove the warnning directly. Signed-off-by: Jason Xing <kernelxing@xxxxxxxxxxx> --- v2 Link: https://lore.kernel.org/all/CAEf4BzaVdr_0kQo=+jPLN++PvcU6pwTjaPVEA880kgDN94TZYw@xxxxxxxxxxxxxx/ 1. use #pragma GCC diagnostic ignored to disable warnning (Andrii Nakryiko) --- samples/bpf/syscall_nrs.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/samples/bpf/syscall_nrs.c b/samples/bpf/syscall_nrs.c index 88f940052450..8f6ae21d358f 100644 --- a/samples/bpf/syscall_nrs.c +++ b/samples/bpf/syscall_nrs.c @@ -2,6 +2,11 @@ #include <uapi/linux/unistd.h> #include <linux/kbuild.h> +#pragma GCC diagnostic push +#ifndef __clang__ +#pragma GCC diagnostic ignored "-Wmissing-prototypes" +#endif + #define SYSNR(_NR) DEFINE(SYS ## _NR, _NR) void syscall_defines(void) -- 2.37.3