Re: How to give compiler arguments

[Martin Martin <martin at infinio dot com>]

Thanks a lot for your help.  I'm exploring the use of systemtap as the
core of a fault injection framework for a user-space program. Having
the probe script be able to modify return codes, local variables and
other values is quite attractive.  I can always put any complicated
functionality in my user application, and have systemtap trigger a
branch into it, e.g. by setting some local variable in my application.

Thanks,
Martin

On Fri, Sep 6, 2013 at 3:00 PM, Josh Stone <jistone@redhat.com> wrote:
> On 09/06/2013 11:42 AM, Martin Martin wrote:
>> Hi,
>>
>> If I put:
>>
>> %{
>> #include "stdint.h"
>> %}
>>
>> at the start of my probe script, stap says:
>>
>>
>> In file included from
>> /tmp/stapR3xMcm/stap_a41ca76a927c0e462ab230035f8677ed_1654_src.c:24:0:
>> /usr/lib/gcc/x86_64-linux-gnu/4.7/include/stdint.h:3:26: error: no
>> include path in which to search for stdint.h
>> make[1]: *** [/tmp/stapR3xMcm/stap_a41ca76a927c0e462ab230035f8677ed_1654_src.o]
>> Error 1
>>
>> Is there a way to give some extra arguments to the compiler to resolve
>> this?  Or am I out of luck because it's a kernel module?
>
> That's the right line of thought -- as a kernel module, stap can only
> include kernel headers.  We do have --runtime=dyninst which runs as a
> shared object, but the usage model is a bit different there.
>
> If "stdint.h" is really what you're after, then "linux/types.h" has a
> lot of the same definitions, and is already included by default.  If
> that's just an example and you're really after some purely userspace
> definitions, you may be out of luck.  However, another option in stap
> functions (not embedded-C) is to use @cast for user types, like:
>
>   @cast(my_pointer, "Elf32_Ehdr", "<elf.h>")->e_machine.
>