Re: [PATCH] perf s390: always build with -fPIC

[Hendrik Brueckner <brueckner@linux.vnet.ibm.com>]

Hi Namhyung,

On Fri, Dec 01, 2017 at 11:17:09AM +0900, Namhyung Kim wrote:
> On Thu, Nov 30, 2017 at 09:49:25AM +0100, Hendrik Brueckner wrote:
> > On s390, object files must be compiled with position-indepedent code
> > in order to be incrementally linked or linked to shared libraries.
> > Therefore, add -fPIC to the CFLAGS for s390 to ensure each object
> > file is built properly.
> 
> Could you please tell me what was the actual problem?  I guess this is
> somewhat related to the Jiri's Fedora build fix.

Building, linking of perf did not work (I think it was on a Fedora 27)
resulting in an error message like:

/usr/bin/ld: perf-in.o: `__printf_chk@@GLIBC_2.4' non-PLT reloc for symbol
defined in shared library and accessed from executable (rebuild file with
-fPIC ?)
/usr/bin/ld: final link failed: Bad value

On s390, objects must be compiled with -fPIC when used for shared object
or position-indendepent executables (PIE). In doubt, it is better to
build with -fPIC (there are no performance degration).

Thanks and kind regards,
  Hendrik