[dpdk-dev] [PATCH v2] mk: fix build ignoring other installed versions

[Thomas Monjalon]

If some DPDK libraries are installed on the system, the linker was trying
to use them before searching in -L path.
The obscure reason is that we were prefixing -L with -Wl, to pass it
directly to the linker.
But -L is also a gcc option. And allowing gcc to process this option fixes
the issue.

Signed-off-by: Thomas Monjalon <thomas.monjalon at 6wind.com>
---
changes since v1:
- automatically remove -Wl from LDLIBS, LDFLAGS and EXTRA_LDFLAGS for -L
- same behavior for rte.app.mk and rte.shared.mk

 mk/internal/rte.build-pre.mk | 3 +++
 mk/rte.app.mk                | 7 +++----
 mk/rte.shared.mk             | 7 +++----
 3 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/mk/internal/rte.build-pre.mk b/mk/internal/rte.build-pre.mk
index d748189..d5ddbfa 100644
--- a/mk/internal/rte.build-pre.mk
+++ b/mk/internal/rte.build-pre.mk
@@ -30,3 +30,6 @@
 #   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 _BUILD_TARGETS := _prebuild _build _postbuild
+
+comma := ,
+linkerprefix = $(subst -Wl$(comma)-L,-L,$(addprefix -Wl$(comma),$1))
diff --git a/mk/rte.app.mk b/mk/rte.app.mk
index 072718a..a2c60b6 100644
--- a/mk/rte.app.mk
+++ b/mk/rte.app.mk
@@ -204,10 +204,9 @@ LDLIBS += -l$(RTE_LIBNAME)
 endif
 
 ifeq ($(LINK_USING_CC),1)
-comma := ,
-LDLIBS := $(addprefix -Wl$(comma),$(LDLIBS))
-LDFLAGS := $(addprefix -Wl$(comma),$(LDFLAGS))
-override EXTRA_LDFLAGS := $(addprefix -Wl$(comma),$(EXTRA_LDFLAGS))
+LDLIBS := $(call linkerprefix,$(LDLIBS))
+LDFLAGS := $(call linkerprefix,$(LDFLAGS))
+override EXTRA_LDFLAGS := $(call linkerprefix,$(EXTRA_LDFLAGS))
 O_TO_EXE = $(CC) $(CFLAGS) $(LDFLAGS_$(@)) \
 	-Wl,-Map=$(@).map,--cref -o $@ $(OBJS-y) $(LDFLAGS) $(EXTRA_LDFLAGS) $(LDLIBS)
 else
diff --git a/mk/rte.shared.mk b/mk/rte.shared.mk
index e9be02d..42feee7 100644
--- a/mk/rte.shared.mk
+++ b/mk/rte.shared.mk
@@ -58,10 +58,9 @@ build: _postbuild
 exe2cmd = $(strip $(call dotfile,$(patsubst %,%.cmd,$(1))))
 
 ifeq ($(LINK_USING_CC),1)
-comma := ,
-LDLIBS := $(addprefix -Wl$(comma),$(LDLIBS))
-LDFLAGS := $(addprefix -Wl$(comma),$(LDFLAGS))
-override EXTRA_LDFLAGS := $(addprefix -Wl$(comma),$(EXTRA_LDFLAGS))
+LDLIBS := $(call linkerprefix,$(LDLIBS))
+LDFLAGS := $(call linkerprefix,$(LDFLAGS))
+override EXTRA_LDFLAGS := $(call linkerprefix,$(EXTRA_LDFLAGS))
 O_TO_SO = $(CC) $(LDFLAGS) $(LDFLAGS_$(@)) $(EXTRA_LDFLAGS) \
 	-shared -o $@ $(OBJS-y) $(LDLIBS)
 else
-- 
1.9.2