From mboxrd@z Thu Jan  1 00:00:00 1970
From: Panu Matilainen <pmatilai@redhat.com>
Subject: Re: [PATCH] mk: fix underlinking issues of most librte
	libraries
Date: Tue, 24 May 2016 12:56:59 +0300
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To: Thomas Monjalon <thomas.monjalon@6wind.com>,
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On 05/20/2016 08:08 PM, Thomas Monjalon wrote:
> 2016-05-20 18:50, Christian Ehrhardt:
>> The individual libraries have various cross dependencies.
>> This is already refelcted in the DEPDIR dependency, but not yet in
>> proper DT_NEEDED flags in the .so's.
>> This adds the -l flags so that is properly stored in the .so's ELF
>> headers.
>
> Why not filling LDLIBS by parsing DEPDIRS-y in rte.lib.mk?
>

A fair question :) The thought has passed my mind too, but I thought 
it'd be too messy with differing library vs directory names and other 
exceptions. But in reality manually maintained separate LDLIBS is only 
going to get out of sync sooner or later, and turns out its not that bad 
anyway:

diff --git a/mk/rte.lib.mk b/mk/rte.lib.mk
index b420280..88b4e98 100644
--- a/mk/rte.lib.mk
+++ b/mk/rte.lib.mk
@@ -77,6 +77,12 @@ else
  _CPU_LDFLAGS := $(CPU_LDFLAGS)
  endif

+# Translate DEPDIRS-y into LDLIBS
+IGNORE_DEPS = -lrte_eal/% -lrte_net -lrte_compat
+_LDDIRS = $(subst librte_ether,libethdev,$(DEPDIRS-y))
+_LDDEPS = $(subst lib/lib,-l,$(_LDDIRS))
+LDLIBS += $(filter-out $(IGNORE_DEPS), $(_LDDEPS))
+
  O_TO_A = $(AR) crDs $(LIB) $(OBJS-y)
  O_TO_A_STR = $(subst ','\'',$(O_TO_A)) #'# fix syntax highlight
  O_TO_A_DISP = $(if $(V),"$(O_TO_A_STR)","  AR $(@)")

I'm also sure somebody more familiar with gmake could improve it, but it 
seems to work quite fine here. I'll wait a bit to see if there are other 
suggestions before sending it as a proper patch.

	- Panu -