Hi, jirka Sadly, we can't include libbpf_internal.h in trace_helpers.{h,c}. we only have the following headers when compile samples/bpf/: tree of samples/bpf/libbpf/ +-- bpf_helper_defs.h +-- include | '-- bpf | +-- bpf_core_read.h | +-- bpf_endian.h | +-- bpf.h | +-- bpf_helper_defs.h | +-- bpf_helpers.h | +-- bpf_tracing.h | +-- btf.h | +-- libbpf_common.h | +-- libbpf.h | +-- libbpf_legacy.h | +-- libbpf_version.h | +-- skel_internal.h | '-- usdt.bpf.h +-- libbpf.a No libbpf_internal.h here. What if we add a declaration to libbpf_ensure_mem() in trace_helpers.c? Good Day, Rong Tao