Re: [PATCH] Test for profiling support (_mcount/gprof)

[Florian Weimer <fweimer at redhat dot com>]

On 08/16/2017 10:03 PM, H.J. Lu wrote:
> On Wed, Aug 16, 2017 at 8:32 AM, Florian Weimer <fweimer@redhat.com> wrote:
>> On 08/16/2017 05:30 PM, Andreas Schwab wrote:
>>> On Aug 16 2017, Florian Weimer <fweimer@redhat.com> wrote:
>>>
>>>> On 08/16/2017 05:20 PM, Andreas Schwab wrote:
>>>>> On Aug 16 2017, Florian Weimer <fweimer@redhat.com> wrote:
>>>>>
>>>>>> If you don't use --enable-frame-pointer for GCC, there's no apparent
>>>>>> reason to me to build glibc with --fomit-frame-pointer because it's the
>>>>>> default (albeit in a fashion that is compatible with -pg).
>>>>>
>>>>> That is not true.
>>>>
>>>> It is currently true—I don't see why anyone would want to build glibc
>>>> this way.  Could you enlighten me?
>>>
>>> To omit the frame pointer.
>>
>> But GCC does it by default if you don't build with
>> --enable-frame-pointer, at least on i386, which is the architecture for
>> which you reported the failure.
> 
> gmon/tst-gmon-gprof also fails with GCC defaulting to PIE.

That would be a real failure (due to ASLR).  Does linking with -pg
ordinarily disable PIE?  I suppose we could add -pg to LDFLAGS for this
test because as Andreas explained earlier, it won't link in the system
profiling libraries.

Thanks,
Florian