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Date:   Sat, 8 May 2021 10:57:45 -0300
From:   Arnaldo Carvalho de Melo <acme@kernel.org>
To:     Song Liu <songliubraving@fb.com>
Cc:     Jiri Olsa <jolsa@kernel.org>, Namhyung Kim <namhyung@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: BUILD_BPF_SKEL error message
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I switched to Fedora 34 Silverblue, and while installing the needed
packages to build perf, using BUILD_BPF_SKEL=1 I noticed this:

Makefile.config:637: *** Error: clang too old. Please install recent clang.  Stop.

The problem is not that clang is too old, its that it is not installed
:-)

Perhaps a slight improvement to state that, something like:

Makefile.config:637: *** Error: clang too old/not installed. Please install recent clang to build with BPF_SKEL.  Stop.

As for a moment I thought clang now was _required_ to build perf, which
isn't the case, it was just me using an alias to build perf:

alias m='make -k BUILD_BPF_SKEL=1 PYTHON=python3 O=/tmp/build/perf -C tools/perf install-bin && perf test python'

Regards,

- Arnaldo