Shahab Vahedi 0b817059a8 bpftool: Fix bootstrapping during a cross compilation
This change adjusts the Makefile to use "HOSTAR" as the archive tool
to keep the sanity of the build process for the bootstrap part in
check. For the rationale, please continue reading.

When cross compiling bpftool with buildroot, it leads to an invocation
like:

$ AR="/path/to/buildroot/host/bin/arc-linux-gcc-ar" \
  CC="/path/to/buildroot/host/bin/arc-linux-gcc"    \
  ...
  make

Which in return fails while building the bootstrap section:

----------------------------------8<----------------------------------

  make: Entering directory '/src/bpftool-v6.7.0/src'
  ...                        libbfd: [ on  ]
  ...        disassembler-four-args: [ on  ]
  ...                          zlib: [ on  ]
  ...                        libcap: [ OFF ]
  ...               clang-bpf-co-re: [ on  ] <-- triggers bootstrap

  .
  .
  .

    LINK     /src/bpftool-v6.7.0/src/bootstrap/bpftool
  /usr/bin/ld: /src/bpftool-v6.7.0/src/bootstrap/libbpf/libbpf.a:
               error adding symbols: archive has no index; run ranlib
               to add one
  collect2: error: ld returned 1 exit status
  make: *** [Makefile:211: /src/bpftool-v6.7.0/src/bootstrap/bpftool]
            Error 1
  make: *** Waiting for unfinished jobs....
    AR       /src/bpftool-v6.7.0/src/libbpf/libbpf.a
    make[1]: Leaving directory '/src/bpftool-v6.7.0/libbpf/src'
    make: Leaving directory '/src/bpftool-v6.7.0/src'

---------------------------------->8----------------------------------

This occurs because setting "AR" confuses the build process for the
bootstrap section and it calls "arc-linux-gcc-ar" to create and index
"libbpf.a" instead of the host "ar".

Signed-off-by: Shahab Vahedi <shahab@synopsys.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Cc: Jean-Philippe Brucker <jean-philippe@linaro.org>
Link: https://lore.kernel.org/bpf/8d297f0c-cfd0-ef6f-3970-6dddb3d9a87a@synopsys.com
2022-06-09 14:01:21 +02:00
2022-06-07 10:20:42 -07:00
2022-06-07 10:20:42 -07:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Description
No description provided
Readme 3.3 GiB
Languages
C 97.5%
Assembly 1%
Shell 0.6%
Python 0.3%
Makefile 0.3%