diff --git a/tools/build/Makefile.build b/tools/build/Makefile.build
index fac42486a8cf..27f4ee9cb4db 100644
--- a/tools/build/Makefile.build
+++ b/tools/build/Makefile.build
@@ -141,6 +141,10 @@ objprefix    := $(subst ./,,$(OUTPUT)$(dir)/)
 obj-y        := $(addprefix $(objprefix),$(obj-y))
 subdir-obj-y := $(addprefix $(objprefix),$(subdir-obj-y))
 
+# Separate out test log files from real build objects.
+test-y       := $(filter %_log, $(obj-y))
+obj-y        := $(filter-out %_log, $(obj-y))
+
 # Final '$(obj)-in.o' object
 in-target := $(objprefix)$(obj)-in.o
 
@@ -151,7 +155,7 @@ $(subdir-y):
 
 $(sort $(subdir-obj-y)): $(subdir-y) ;
 
-$(in-target): $(obj-y) FORCE
+$(in-target): $(obj-y) $(test-y) FORCE
 	$(call rule_mkdir)
 	$(call if_changed,$(host)ld_multi)