[systemtap trunk] Build error on eBPF.

[Richard Henderson]

On 04/14/2017 04:57 AM, Mark Wielaard wrote:
> On Fri, 2017-04-14 at 20:17 +0900, Tetsuo Handa wrote:
>> Mark Wielaard wrote:
>>> On Wed, 2017-04-12 at 23:24 +0900, Tetsuo Handa wrote:
>>>> Commit 7e2cd9f56293f697 ("Squashed commit of the eBPF backend for stap")
>>>> caused following build error when trying to build on CentOS 7.
>>>
>>> Older GCC versions seemed to have some trouble with initialization of
>>> anonymous struct fields in unions. Older elfutils didn't provide some
>>> strtab manipulation functions. And some older kernel headers didn't
>>> define all needed constants.
>>>
>>> I pushed the following commits to hopefully fix the compilation (I
>>> haven't tested running the ebpf backend yet):
>>
>>> Could you check if that helps in your case (my setup isn't really a pure
>>> CentOS7 one).
>>
>> Thank you. But linux/bpf.h check seems to be missing.
>
> Aha. Seems I have a slightly older version than Richard tested with, but
> you don't have it at all. Could you try to update your git sources with
> this commit:
>
> commit 7ca1ffe6e431e4818a9a479935d75a428d2aaf57
> Author: Mark Wielaard <mark@klomp.org>
> Date:   Fri Apr 14 13:52:39 2017 +0200
>
>     configure: Check for linux/bpf.h header.
>
>     Don't build bpf backend support if there is no bpf.h header.
>     Skip translate_bpf_pass if there is no bpf support.
>     Regenerate configure and Makefile.in.
>
> It should completely skip building the bpf backend in your case.

Thanks, Mark.


r~