Re: [PATCH v2 bpf-next 1/4] bpftool: generate NULL definition in vmlinux.h

On Wed, Mar 17, 2021 at 10:38 AM Andrii Nakryiko
[off-list ref] wrote:

quoted

diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c
index 62953bbf68b4..ff6a76632873 100644
--- a/tools/bpf/bpftool/btf.c
+++ b/tools/bpf/bpftool/btf.c

@@ -405,6 +405,8 @@ static int dump_btf_c(const struct btf *btf,
        printf("#ifndef __VMLINUX_H__\n");
        printf("#define __VMLINUX_H__\n");
        printf("\n");
+       printf("#define NULL ((void *)0)\n");

On second thought, this could also be done in bpf_helpers.h, which is
pretty much always included in BPF programs. I think that's a bit more
maintainable and less magical to users, so I'll go with that in v3.

yep. good idea.