Re: [PATCH 2/2] perf: unwinding: use the per-feature check flags

[Jiri Olsa <jolsa@redhat.com>]

On Tue, Dec 10, 2013 at 11:05:04AM +0100, Jean Pihet wrote:
> Hi Jiri,
> 
> On 10 December 2013 10:57, Jiri Olsa <jolsa@redhat.com> wrote:
> > On Mon, Dec 09, 2013 at 07:02:02PM +0100, Jean Pihet wrote:
> >> Hi Jiri,
> >>
> >> On 9 December 2013 18:17, Jiri Olsa <jolsa@redhat.com> wrote:
> >> > On Sat, Dec 07, 2013 at 11:17:41AM +0100, Jean Pihet wrote:
> >> >> Use the per-feature check flags for the unwinding feature in order
> >> >> to correctly compile the libunwind and libunwind-debug-frame feature
> >> >> checks.
> >> >>
> >> >> Tested on x86_64, ARMv7 and ARMv8 with and without LIBUNWIND_DIR set
> >> >> in 'make -C tools/perf'
> >> >>
> >> >> Signed-off-by: Jean Pihet <jean.pihet@linaro.org>
> >> >> Cc: Jiri Olsa <jolsa@redhat.com>
> >> >
> >> > SNIP
> >> >
> >> >> +BUILD = $(CC) $(CFLAGS) -o $(OUTPUT)$@ $@.c $(LDFLAGS)
> >> >>
> >> >>  ###############################
> >> >>
> >> >>  test-all:
> >> >> -     $(BUILD) -Werror -fstack-protector -fstack-protector-all -O2 -Werror -D_FORTIFY_SOURCE=2 -ldw -lelf -lnuma $(LIBUNWIND_LIBS) -lelf -laudit -I/usr/include/slang -lslang $(shell pkg-config --libs --cflags gtk+-2.0 2>/dev/null) $(FLAGS_PERL_EMBED) $(FLAGS_PYTHON_EMBED) -DPACKAGE='"perf"' -lbfd -ldl
> >> >> +     $(BUILD) -Werror -fstack-protector -fstack-protector-all -O2 -Werror -D_FORTIFY_SOURCE=2 -ldw -lelf -lnuma -lelf -laudit -I/usr/include/slang -lslang $(shell pkg-config --libs --cflags gtk+-2.0 2>/dev/null) $(FLAGS_PERL_EMBED) $(FLAGS_PYTHON_EMBED) -DPACKAGE='"perf"' -lbfd -ldl
> >> >
> >> > hum, the test-all build command should have every possible flags we use, right?
> >> > including LIBUNWIND_CFLAGS, LIBUNWIND_LDFLAGS
> >> Oh yes you are right. I am overlooked the test-all feature (which
> >> never builds on my modest embedded systems).
> >> $(LIBUNWIND_LIBS) should be replaced by $(LIBUNWIND_CFLAGS)
> >> $(LIBUNWIND_LDFLAGS), is that a reasonable approach?
> >
> > hum, I'm just dealing with same issue for new libdw feature.. ;-)
> >
> > I was wondering we could just setup:
> >   FEATURE_CHECK_CFLAGS-all
> >   FEATURE_CHECK_LDFLAGS-all
> >
> > automatically from all defined FEATURE_CHECK_(C|LD)FLAGS-*
> > just a thought.. haven't tried it yet
> Yes that is the idea. The per-feature flags are designed for that
> purpose. For now I have the fix for libunwind only, cf. here below.
> All features should use the flags. There are complex cases though (e.g
> perl flags in config/Makefile andconfig/feature-checks)...
> 
> My plan is to submit the ix for libunwind first and if ok care about
> the other features. Is that OK?

sounds good, thanks

jirka