[bpf-next,v3] bpf: syscall_nrs: disable no previous prototype warnning

Commit Message

Jason Xing Oct. 1, 2024, 11:32 p.m. UTC

From: Jason Xing <[e-mail]>

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 <[e-mail]>
---
v3
Link: https://lore.kernel.org/all/[e-mail]/
1. remove clang check (Andrii)
2. add matching pop at the bottom of that file (Andrii)

v2
Link: https://lore.kernel.org/all/CAEf4BzaVdr_0kQo=[e-mail]/
1. use #pragma GCC diagnostic ignored to disable warnning (Andrii Nakryiko)
---
 samples/bpf/syscall_nrs.c | 5 +++++
 1 file changed, 5 insertions(+)

Comments

Jason Xing Oct. 8, 2024, 12:59 a.m. UTC | #1

On Wed, Oct 2, 2024 at 7:32 AM Jason Xing <[e-mail]> wrote:
>
> From: Jason Xing <[e-mail]>
>
> 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 <[e-mail]>

Hello Andrii,

Could you help me review this version?

Thanks,
Jason

[e-mail] Oct. 8, 2024, 3:30 a.m. UTC | #2

Hello:

This patch was applied to bpf/bpf-next.git (master)
by Andrii Nakryiko <[e-mail]>:

On Wed,  2 Oct 2024 07:32:42 +0800 you wrote:
> From: Jason Xing <[e-mail]>
> 
> 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)
>         ^~~~~~~~~~~~~~~
> 
> [...]

Here is the summary with links:
  - [bpf-next,v3] bpf: syscall_nrs: disable no previous prototype warnning
    https://git.kernel.org/bpf/bpf-next/c/c50fc1cbfd71

You are awesome, thank you!

Patch

diff --git a/samples/bpf/syscall_nrs.c b/samples/bpf/syscall_nrs.c
index 88f940052450..a6e600f3d477 100644
--- a/samples/bpf/syscall_nrs.c
+++ b/samples/bpf/syscall_nrs.c
@@ -2,6 +2,9 @@ 
 #include <uapi/linux/unistd.h>
 #include <linux/kbuild.h>
 
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wmissing-prototypes"
+
 #define SYSNR(_NR) DEFINE(SYS ## _NR, _NR)
 
 void syscall_defines(void)
@@ -17,3 +20,5 @@  void syscall_defines(void)
 #endif
 
 }
+
+#pragma GCC diagnostic pop