I can make minimal，but can't make bpftool，why？

[Ruid6]

Ubuntu 22.04 LTS：6.8.0-40-generic

I've read the Readme

apt install clang libelf1 libelf-dev zlib1g-dev
git clone --recurse-submodules https://github.com/libbpf/libbpf-bootstrap
git submodule update --init --recursive
cd examples/c
make

OUTPUT:

MKDIR .output
MKDIR .output/libbpf
LIB libbpf.a
make[1]: pkg-config: 没有那个文件或目录
MKDIR /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/bpf.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/btf.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/libbpf.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/libbpf_errno.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/netlink.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/nlattr.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/str_error.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/libbpf_probes.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/bpf_prog_linfo.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/btf_dump.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/hashmap.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/ringbuf.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/strset.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/linker.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/gen_loader.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/relo_core.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/usdt.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/zip.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/elf.o
CC /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/staticobjs/features.o
AR /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/libbpf.a
INSTALL bpf.h libbpf.h btf.h libbpf_common.h libbpf_legacy.h bpf_helpers.h bpf_helper_defs.h bpf_tracing.h bpf_endian.h bpf_core_read.h skel_internal.h libbpf_version.h usdt.bpf.h
INSTALL /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/libbpf.pc
INSTALL /home/ruid/libbpf-bootstrap/examples/c/.output//libbpf/libbpf.a
MKDIR bpftool
BPFTOOL bpftool/bootstrap/bpftool
... libbfd: [ OFF ]
... clang-bpf-co-re: [ on ]
... llvm: [ OFF ]
... libcap: [ OFF ]
MKDIR /home/ruid/libbpf-bootstrap/examples/c/.output/bpftool/bootstrap/libbpf/include/bpf
INSTALL /home/ruid/libbpf-bootstrap/examples/c/.output/bpftool/bootstrap/libbpf/include/bpf/hashmap.h
INSTALL /home/ruid/libbpf-bootstrap/examples/c/.output/bpftool/bootstrap/libbpf/include/bpf/relo_core.h
INSTALL /home/ruid/libbpf-bootstrap/examples/c/.output/bpftool/bootstrap/libbpf/include/bpf/libbpf_internal.h
MKDIR /home/ruid/libbpf-bootstrap/examples/c/.output/bpftool/bootstrap/
MKDIR /home/ruid/libbpf-bootstrap/examples/c/.output/bpftool/bootstrap/libbpf/
make[2]: pkg-config: 没有那个文件或目录
......

But, sudo ./bootstrap work successfully.
Than , cd bpftool/src && make

... libbfd: [ OFF ]
... clang-bpf-co-re: [ on ]
... llvm: [ OFF ]
... libcap: [ OFF ]
GEN pid_iter.skel.h
CC pids.o
CLANG profiler.bpf.o
make: llvm-strip: 没有那个文件或目录
make: *** [Makefile:209：profiler.bpf.o] 错误 127

What's wrong with me?

[anakryiko]

Nothing is wrong with you :) full-blown bpftool expects llvm-strip (for no good reason, anymore), so make sure you have that tool available.

cc @qmonnet, it would be nice to remove llvm-strip, bpftool gen object strips out DWARF already, so you shouldn't need extra stripping.

[qmonnet]

Hey! I can't even remember why we have it. Looking at the logs, you added it in torvalds/linux@f3c93a9, but if now we strip it already then I guess the command brings nothing and yes, I'll remove it (give me a few days)

[qmonnet]

The llvm-strip pass was removed in bpf-next's bpftool, the patch will land in the GH repo at the next sync.
https://lore.kernel.org/all/20240924165202.1379930-1-chen.dylane@gmail.com/t/#m2c7d090d88b405495d05b0f3d191a9afe76bb49e