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

[Namhyung Kim <namhyung@kernel.org>]

On Wed, 30 Jan 2013 04:28:31 +0100, Borislav Petkov wrote:
> On Wed, Jan 30, 2013 at 11:15:55AM +0900, Namhyung Kim wrote:
>> Please see my reply on another post from Thomas:
>> 
>>   https://lkml.org/lkml/2013/1/29/32
>> 
>> It's not like a build failure of perf tools, it's just a result of
>> feature test so should not affect the build of perf itself, right?
>
> Doh, I see it. It is the -DHAVE_STRLCPY test, of course. And it happens
> only with a V=1 build, so actually there's not a build problem.
>
>> Why it confuses us is that we don't show any compile message if -s
>> option is given to make, so I posted a patch to hide CHK and above
>> failure message when -s option is specified.
>
> Hm, trying your patch ontop of acme's perf/core still shows CHK stuff
>
> $ make -s tools/perf
>     DESCEND perf
>     CHK -fstack-protector-all
>     CHK -Wstack-protector
>     CHK -Wvolatile-register-var
>     CHK bionic
>     CHK libelf
>     CHK libdw
>     ...
>
>
> and that's because I'm doing the build from the toplevel repo and not in
> perf/. If I switch to perf first, it is silent:
>
> $ make -s
> Makefile:809: No bfd.h/libbfd found, install binutils-dev[el]/zlib-static to gain symbol demangling
> Makefile:846: No numa.h found, disables 'perf bench numa mem' benchmark, please install numa-libs-devel or libnuma-dev
> $

That's because the toplevel Makefile resets MAKEFLAGS in the middle:

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

Thanks,
Namhyung