Subject: [PATCH 0/7] libbpf: Fix cast away const qualifiers in btf.h

From: Jiri Olsa <[email-masked]>
Date: Fri, 6 Sep 2019 09:31:37 +0200

hi,
when including btf.h in bpftrace, I'm getting -Wcast-qual warnings like:

  bpf/btf.h: In function ‘btf_var_secinfo* btf_var_secinfos(const btf_type*)’:
  bpf/btf.h:302:41: warning: cast from type ‘const btf_type*’ to type
  ‘btf_var_secinfo*’ casts away qualifiers [-Wcast-qual]
    302 |  return (struct btf_var_secinfo *)(t + 1);
        |                                         ^

I changed the btf.h header to comply with -Wcast-qual checks
and used const cast away casting in libbpf objects, where it's
all related to deduplication code, so I believe loosing const
is fine there.

thanks,
jirka

---
Jiri Olsa (7):
      libbpf: Use const cast for btf_int_* functions
      libbpf: Return const btf_array from btf_array inline function
      libbpf: Return const btf_enum from btf_enum inline function
      libbpf: Return const btf_member from btf_members inline function
      libbpf: Return const btf_param from btf_params inline function
      libbpf: Return const btf_var from btf_var inline function
      libbpf: Return const struct btf_var_secinfo from btf_var_secinfos inline function

 tools/lib/bpf/btf.c    | 21 +++++++++++----------
 tools/lib/bpf/btf.h    | 30 +++++++++++++++---------------
 tools/lib/bpf/libbpf.c |  2 +-
 3 files changed, 27 insertions(+), 26 deletions(-)