Em Wed, Oct 21, 2020 at 08:35:34AM -0700, Andrii Nakryiko escreveu: > On Fri, Oct 9, 2020 at 12:26 PM Andrii Nakryiko <andrii@xxxxxxxxxx> wrote: > > > > Differentiate between struct and union forwards. For BTF_KIND_FWD this is > > determined by kflag. So teach btf_loader to use that bit to decide whether > > forward is for union or struct. > > > > Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx> > > --- > > N.B. This patch is based on top of tmp.libbtf_encoder branch. > > > > Also seems like non-forward declared union has a slightly different > > representation from struct (class). Not sure why it is so, but this change > > doesn't seem to break anything. > > --- > > Ping on this one, let's include it with upcoming pahole 1.19 as well? I missed this one, but please consider providing concrete examples, can you provide one so that its completely spelled out, like for a 4.9yo kid? 8-) - Arnaldo > > > > btf_loader.c | 9 +++++---- > > 1 file changed, 5 insertions(+), 4 deletions(-) > > > > diff --git a/btf_loader.c b/btf_loader.c > > index 9b5da3a4997a..0cb23967fec3 100644 > > --- a/btf_loader.c > > +++ b/btf_loader.c > > @@ -134,12 +134,13 @@ static struct type *type__new(uint16_t tag, strings_t name, size_t size) > > return type; > > } > > > > -static struct class *class__new(strings_t name, size_t size) > > +static struct class *class__new(strings_t name, size_t size, bool is_union) > > { > > struct class *class = tag__alloc(sizeof(*class)); > > + uint32_t tag = is_union ? DW_TAG_union_type : DW_TAG_structure_type; > > > > if (class != NULL) { > > - type__init(&class->type, DW_TAG_structure_type, name, size); > > + type__init(&class->type, tag, name, size); > > INIT_LIST_HEAD(&class->vtable); > > } > > > > @@ -228,7 +229,7 @@ static int create_members(struct btf_elf *btfe, const struct btf_type *tp, > > > > static int create_new_class(struct btf_elf *btfe, const struct btf_type *tp, uint32_t id) > > { > > - struct class *class = class__new(tp->name_off, tp->size); > > + struct class *class = class__new(tp->name_off, tp->size, false); > > int member_size = create_members(btfe, tp, &class->type); > > > > if (member_size < 0) > > @@ -313,7 +314,7 @@ static int create_new_subroutine_type(struct btf_elf *btfe, const struct btf_typ > > > > static int create_new_forward_decl(struct btf_elf *btfe, const struct btf_type *tp, uint32_t id) > > { > > - struct class *fwd = class__new(tp->name_off, 0); > > + struct class *fwd = class__new(tp->name_off, 0, btf_kind(tp)); > > > > if (fwd == NULL) > > return -ENOMEM; > > -- > > 2.24.1 > > -- - Arnaldo