Build RS compatibility objects with libcompiler-rt.a.

Change-Id: Ic49fdc30b1d4568bbdc94338e116a31a1ade1e80
diff --git a/core/definitions.mk b/core/definitions.mk
index e216a70..1b55564 100644
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -826,7 +826,9 @@
 	-rt-path $(PRIVATE_LIBCLCORE) $<
 $(hide) $(PRIVATE_CXX) -shared -Wl,-soname,$(notdir $@) -nostdlib \
 	-Wl,-rpath,\$$ORIGIN/../lib \
-	$(dir $@)/$(notdir $(<:.bc=.o)) -o $@ -L prebuilts/gcc/ \
+	$(dir $@)/$(notdir $(<:.bc=.o)) \
+	$(PRIVATE_COMPILER_RT) \
+	-o $@ -L prebuilts/gcc/ \
 	-L $(TARGET_OUT_INTERMEDIATE_LIBRARIES) -lRSSupport -lm
 endef