diff --git a/x86/Makefile.common b/x86/Makefile.common
index 5567d66..b942086 100644
--- a/x86/Makefile.common
+++ b/x86/Makefile.common
@@ -72,7 +72,7 @@
 	$(CC) -m32 -nostdlib -o $@ -Wl,-m,elf_i386 \
 	      -Wl,-T,$(SRCDIR)/$(TEST_DIR)/realmode.lds $^
 
-$(TEST_DIR)/realmode.o: bits = 16
+$(TEST_DIR)/realmode.o: bits = $(if $(call cc-option,-m16,""),16,32)
 
 $(TEST_DIR)/kvmclock_test.elf: $(TEST_DIR)/kvmclock.o