On 4/1/24 10:07, Andrii Nakryiko wrote:
When generated BPF skeleton header is included in C++ code base, some compiler setups will emit warning about using language extensions due to typeof() usage, resulting in something like: error: extension used [-Werror,-Wlanguage-extension-token] obj->struct_ops.empty_tcp_ca = (typeof(obj->struct_ops.empty_tcp_ca)) ^ It looks like __typeof__() is a preferred way to do typeof() with better C++ compatibility behavior, so switch to that. With __typeof__() we get no such warning. Fixes: c2a0257c1edf ("bpftool: Cast pointers for shadow types explicitly.") Fixes: 00389c58ffe9 ("bpftool: Add support for subskeletons") Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx> --- tools/bpf/bpftool/gen.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index 786268f1a483..b3979ddc0189 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -386,7 +386,7 @@ static int codegen_subskel_datasecs(struct bpf_object *obj, const char *obj_name */ needs_typeof = btf_is_array(var) || btf_is_ptr_to_func_proto(btf, var); if (needs_typeof) - printf("typeof("); + printf("__typeof__(");err = btf_dump__emit_type_decl(d, var_type_id, &opts);if (err) @@ -1131,7 +1131,7 @@ static void gen_st_ops_shadow_init(struct btf *btf, struct bpf_object *obj) continue; codegen("\ \n\ - obj->struct_ops.%1$s = (typeof(obj->struct_ops.%1$s))\n\ + obj->struct_ops.%1$s = (__typeof__(obj->struct_ops.%1$s))\n\ bpf_map__initial_value(obj->maps.%1$s, NULL);\n\ \n\ ", ident);
LGTM! Acked-by: Kui-Feng Lee <thinker.li@xxxxxxxxx> Thanks!
