[PATCH for vm-scalability] Makefile: Add static build option

[Hui Zhu]

Sometimes vm-scalability needs to work in an environment without an
libraries.  Supporting static build is helpful.

This commit add static build option:
make STATIC=1

Signed-off-by: Hui Zhu <teawaterz@xxxxxxxxxxxxxxxxx>
---
 Makefile | 27 +++++++++++++++++----------
 1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/Makefile b/Makefile
index 73b2ff3..eadc090 100644
--- a/Makefile
+++ b/Makefile
@@ -6,6 +6,13 @@ EXECUTABLES :=	usemem \
 		usemem_direct_write \
 		usemem_mbind
 
+ifdef STATIC
+	EXTRA_LDFLAGS := -static
+else
+	EXTRA_LDFLAGS :=
+endif
+
+
 all:	$(EXECUTABLES)
 
 clean:
@@ -15,31 +22,31 @@ distclean: clean
 	rm -f $(EXECUTABLES)
 
 usemem: usemem.o usemem_hugepages.o usemem_mincore.o
-	gcc -pthread -Wall -O -g usemem_mincore.o usemem_hugepages.o usemem.o -o usemem
+	gcc -pthread -Wall -O -g $(EXTRA_LDFLAGS) usemem_mincore.o usemem_hugepages.o usemem.o -o usemem
 
 usemem.o: usemem.c
-	gcc -O -c -Wall -g  usemem.c -o usemem.o
+	gcc -O -c -Wall -g $(EXTRA_LDFLAGS) usemem.c -o usemem.o
 
 usemem_hugepages.o: usemem_hugepages.c
-	gcc -Wall -O -c -g usemem_hugepages.c -o usemem_hugepages.o
+	gcc -Wall -O -c -g $(EXTRA_LDFLAGS) usemem_hugepages.c -o usemem_hugepages.o
 
 usemem_mincore.o: usemem_mincore.c
-	gcc -Wall -O -c -g usemem_mincore.c -o usemem_mincore.o
+	gcc -Wall -O -c -g $(EXTRA_LDFLAGS) usemem_mincore.c -o usemem_mincore.o
 
 usemem_migrate: usemem_migrate.c
-	gcc -Wall -O -g -o usemem_migrate usemem_migrate.c -lnuma
+	gcc -Wall -O -g $(EXTRA_LDFLAGS) -o usemem_migrate usemem_migrate.c -lnuma
 
 usemem_ksm: usemem_ksm.c usemem_hugepages.c
-	gcc -Wall -g -o usemem_ksm usemem_ksm.c usemem_hugepages.c
+	gcc -Wall -g $(EXTRA_LDFLAGS) -o usemem_ksm usemem_ksm.c usemem_hugepages.c
 
 usemem_mbind: usemem_mbind.c
-	gcc -Wall -g -o usemem_mbind usemem_mbind.c -lnuma
+	gcc -Wall -g $(EXTRA_LDFLAGS) -o usemem_mbind usemem_mbind.c -lnuma
 
 usemem_ksm_hugepages: usemem_ksm_hugepages.c
-	gcc -Wall -g -o usemem_ksm_hugepages usemem_ksm_hugepages.c
+	gcc -Wall -g $(EXTRA_LDFLAGS) -o usemem_ksm_hugepages usemem_ksm_hugepages.c
 
 usemem_direct_write: usemem_direct_write.c
-	gcc -Wall -g -o usemem_direct_write usemem_direct_write.c
+	gcc -Wall -g $(EXTRA_LDFLAGS) -o usemem_direct_write usemem_direct_write.c
 
 usemem_remap: usemem_remap.c
-	gcc -Wall -g -o usemem_remap usemem_remap.c
+	gcc -Wall -g $(EXTRA_LDFLAGS) -o usemem_remap usemem_remap.c
-- 
2.7.4