diff --git a/Makefile.top b/Makefile.top
index bed77fb918df..f497407b3467 100644
--- a/Makefile.top
+++ b/Makefile.top
@@ -453,6 +453,9 @@ findunusedcode:
 	@which callcatcher > /dev/null 2>&1 || \
 	    (echo "callcatcher not installed" && false)
 	@sed -e s,$$INPATH,callcatcher,g $(SRCDIR)/config_host.mk | sed -e s,"export OOO_JUNIT_JAR=.*","export OOO_JUNIT_JAR=",g > $(SRCDIR)/config_host_callcatcher.mk
+	@echo unexport ARCH_FLAGS >> $(SRCDIR)/config_host_callcatcher.mk
+	@echo unexport CFLAGS >> $(SRCDIR)/config_host_callcatcher.mk
+	@echo unexport CXXFLAGS >> $(SRCDIR)/config_host_callcatcher.mk
 	@mkdir -p $(SRCDIR)/solenv/callcatcher/bin && \
 	    ln -sf $(SRCDIR)/solenv/$(INPATH)/bin/dmake \
 		$(SRCDIR)/solenv/callcatcher/bin/dmake