Build static libs without -fPIC and only if BUILD_STATIC=yes

https://bugs.gentoo.org/379849

Patch written by Kacper Kowalik <xarthisius@gentoo.org>
--- a/Makefile
+++ b/Makefile
@@ -7,6 +7,8 @@
 # for compatibility with old releases
 CFLAGS += ${OPT_CFLAGS}
 override CFLAGS += -I.
+# build static libraries by default
+BUILD_STATIC ?= yes
 
 # find out if compiler supports __thread
 THREAD_SUPPORT := $(shell if $(CC) $(CFLAGS) threadtest.c -o threadtest \
@@ -24,6 +26,7 @@
 
 CLEANFILES := numactl.o libnuma.o numactl numademo numademo.o distance.o \
 	      memhog libnuma.so libnuma.so.1 numamon numamon.o syscall.o bitops.o \
+	      distance.pic.o libnuma.pic.o syscall.pic.o \
 	      memhog.o util.o stream_main.o stream_lib.o shm.o stream clearcache.o \
 	      test/pagesize test/tshared test/mynode.o test/tshared.o mt.o empty.o empty.c \
 	      test/mynode test/ftok test/prefered test/randmap \
@@ -40,11 +43,16 @@
 libdir := ${prefix}/$(shell ./getlibdir)
 docdir := ${prefix}/share/doc
 
+NUMA_LIBS = libnuma.so
+ifeq ($(BUILD_STATIC),yes)
+NUMA_LIBS+= libnuma.a
+endif
+
 all: numactl migratepages migspeed libnuma.so numademo numamon memhog \
      test/tshared stream test/mynode test/pagesize test/ftok test/prefered \
      test/randmap test/nodemap test/distance test/tbitmap test/move_pages \
      test/mbind_mig_pages test/migrate_pages test/realloc_test libnuma.a \
-     test/node-parse numastat
+     test/node-parse numastat ${NUMA_LIBS}
 
 numactl: numactl.o util.o shm.o bitops.o libnuma.so
 
@@ -81,13 +89,14 @@
 
 libnuma.so.1: versions.ldscript
 
-libnuma.so.1: libnuma.o syscall.o distance.o affinity.o sysfs.o rtnetlink.o
+libnuma.so.1: libnuma.pic.o syscall.pic.o distance.pic.o affinity.pic.o sysfs.pic.o rtnetlink.pic.o
 	${CC} ${LDFLAGS} -shared -Wl,-soname=libnuma.so.1 -Wl,--version-script,versions.ldscript -Wl,-init,numa_init -Wl,-fini,numa_fini -o libnuma.so.1 $(filter-out versions.ldscript,$^)
 
 libnuma.so: libnuma.so.1
 	ln -sf libnuma.so.1 libnuma.so
 
-libnuma.o : CFLAGS += -fPIC
+%.pic.o: %.c
+	${CC} -fPIC ${CPPFLAGS} ${CFLAGS} -c $< -o $@
 
 AR ?= ar
 RANLIB ?= ranlib
@@ -95,16 +104,6 @@
 	$(AR) rc $@ $^
 	$(RANLIB) $@
 
-distance.o : CFLAGS += -fPIC
-
-syscall.o : CFLAGS += -fPIC
-
-affinity.o : CFLAGS += -fPIC
-
-sysfs.o : CFLAGS += -fPIC
-
-rtnetlink.o : CFLAGS += -fPIC
-
 test/tshared: test/tshared.o libnuma.so
 
 test/mynode: test/mynode.o libnuma.so
@@ -143,7 +148,9 @@
 	mkdir -p ${libdir}
 	install -m 0755 libnuma.so.1 ${libdir}
 	cd ${libdir} ; ln -sf libnuma.so.1 libnuma.so
+ifeq ($(BUILD_STATIC),yes)
 	install -m 0644 libnuma.a ${libdir}
+endif
 	mkdir -p ${prefix}/include
 	install -m 0644 numa.h numaif.h numacompat1.h ${prefix}/include
 	install -m 0755 numastat ${prefix}/bin