Re: perf 3.8-rc build failure: undefined reference to `strlcpy'

[Borislav Petkov <bp@alien8.de>]

On Wed, Jan 30, 2013 at 01:56:34PM +0900, Namhyung Kim wrote:
> That's because the toplevel Makefile resets MAKEFLAGS in the middle:

That was me: ea01fa9f63aef

> 
> Makefile:1330
>   # Clear a bunch of variables before executing the submake

and I added this because there was a problem AFAICR. And why I added it,
is not documented in the patch commit message, crap.

>   tools/: FORCE
>   	$(Q)mkdir -p $(objtree)/tools
>   	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS= O=$(objtree) subdir=tools -C $(src)/tools/
>   
>   tools/%: FORCE
>   	$(Q)mkdir -p $(objtree)/tools
>   	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS= O=$(objtree) subdir=tools -C $(src)/tools/ $*
>
> So why should it be reset in the first place?

Oh yeah, it was some interaction with the toplevel Makefile that caused
issues. Here's one, if you remove MAKEFLAGS= above and dump it in the
target, here's what you get:

$ make -j9 tools/perf_clean
MAKEFLAGS: --no-print-directory -Rr --jobserver-fds=5,7 -j -I /w/kernel/linux-2.6
    DESCEND perf
make[2]: warning: jobserver unavailable: using -j1.  Add `+' to parent make rule.
    SUBDIR ../lib/traceevent/
*.o *~ libtraceevent.a libtraceevent.so *.a *.so ep_version.h .*.d
/bin/sh: 1: *.o: not found
make[4]: *** [clean] Error 127
make[3]: *** [sub-make] Error 2
make[2]: *** [/w/kernel/linux-2.6/tools/perf/libtraceevent.a-clean] Error 2
make[1]: *** [perf_clean] Error 2
make: *** [tools/perf_clean] Error 2

The "rm -f" is missing at the beginning of the line because kbuild does
remove build files differently.

If you leave it in, it works fine:

    DESCEND perf
    SUBDIR ../lib/traceevent/
rm -f *.o *~ libtraceevent.a libtraceevent.so *.a *.so ep_version.h .*.d
...

> > Oh, and one more thing, there's tools/scripts/Makefile.include which
> > looks at -s already and perf/Makefile includes it so you probably want
> > to put your change there so that all tools use it.
> 
> Are you suggesting that moving "try-cc" to the Makefile.include?

Forget it, I got confused with the QUIET_* thingies in
<tools/scripts/Makefile.include>

Thanks.

-- 
Regards/Gruss,
    Boris.

Sent from a fat crate under my desk. Formatting is fine.
--