Re: gcc-5: error: -gz is not supported in this configuration

[Fangrui Song]

On 2020-06-09, Nick Desaulniers wrote:
> On Tue, Jun 9, 2020 at 6:12 AM kernel test robot <lkp@xxxxxxxxx> wrote:
> > tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> > head:   abfbb29297c27e3f101f348dc9e467b0fe70f919
> > commit: 10e68b02c861ccf2b3adb59d3f0c10dc6b5e3ace Makefile: support compressed debug info
> > date:   12 days ago
> > config: x86_64-randconfig-r032-20200609 (attached as .config)
> > compiler: gcc-5 (Ubuntu 5.5.0-12ubuntu1) 5.5.0 20171010
> > reproduce (this is a W=1 build):
> >         git checkout 10e68b02c861ccf2b3adb59d3f0c10dc6b5e3ace
> >         # save the attached .config to linux build tree
> >         make W=1 ARCH=x86_64
> >
> > If you fix the issue, kindly add following tag as appropriate
> > Reported-by: kernel test robot <lkp@xxxxxxxxx>
> >
> > All errors (new ones prefixed by >>, old ones prefixed by <<):
> >
> > >> gcc-5: error: -gz is not supported in this configuration
>
> Hmm...I wonder if the feature detection is incomplete?  I suspect it's
> possible to not depend on zlib.
>
> > make[2]: *** [scripts/Makefile.build:277: scripts/mod/empty.o] Error 1
> > make[2]: Target '__build' not remade because of errors.
> > make[1]: *** [Makefile:1169: prepare0] Error 2
> > make[1]: Target 'prepare' not remade because of errors.
> > make: *** [Makefile:185: __sub-make] Error 2

The output of gcc-5 -v --version on that machine may help.  The
convoluted gcc_cv_ld_compress_de logic in gcc/configure.ac may be
related, but I can't find any mistake that our
CONFIG_DEBUG_INFO_COMPRESSED conditions may make.