[OE-core] [PATCH] perf: Add LDFLAGS to allow build of old kernels without patching

[Enrico Scholz]

Otavio Salvador <otavio-fKevB0iiKLMBZ+LybsDmbA at public.gmane.org> writes:

> +# The LDFLAGS is required or some old kernels fails due missing
> +# symbols and this is preferred than requiring patches to every old
> +# supported kernel.
> +LDFLAGS="-ldl -lutil"

LDFLAGS is usually the wrong variable for extra libs (it might conflict
with '-Wl,-as-needed' or lib-grouping).  Adding new libs to perf seems
to require the modification of EXTLIBS because of

| LIBS = -Wl,--whole-archive $(PERFLIBS) -Wl,--no-whole-archive -Wl,--start-group $(EXTLIBS) -Wl,--end-group
| ...
|$(OUTPUT)perf-%: %.o $(PERFLIBS)
|	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(LIBS)



Enrico