diff --git a/src/Makefile.bench.include b/src/Makefile.bench.include
index 840d33c1b..246797a1b 100644
--- a/src/Makefile.bench.include
+++ b/src/Makefile.bench.include
@@ -67,7 +67,9 @@ bitcoin_bench_clean : FORCE
 
 %.raw.h: %.raw
 	@$(MKDIR_P) $(@D)
-	@echo "static unsigned const char $(*F)[] = {" >> $@
-	@$(HEXDUMP) -v -e '8/1 "0x%02x, "' -e '"\n"' $< | $(SED) -e 's/0x  ,//g' >> $@
-	@echo "};" >> $@
+	@{ \
+	 echo "static unsigned const char $(*F)[] = {" && \
+	 $(HEXDUMP) -v -e '8/1 "0x%02x, "' -e '"\n"' $< | $(SED) -e 's/0x  ,//g' && \
+	 echo "};"; \
+	} > "$@.new" && mv -f "$@.new" "$@"
 	@echo "Generated $@"
diff --git a/src/Makefile.test.include b/src/Makefile.test.include
index fa610e300..a14adc787 100644
--- a/src/Makefile.test.include
+++ b/src/Makefile.test.include
@@ -149,16 +149,10 @@ endif
 
 %.json.h: %.json
 	@$(MKDIR_P) $(@D)
-	@echo "namespace json_tests{" > $@
-	@echo "static unsigned const char $(*F)[] = {" >> $@
-	@$(HEXDUMP) -v -e '8/1 "0x%02x, "' -e '"\n"' $< | $(SED) -e 's/0x  ,//g' >> $@
-	@echo "};};" >> $@
-	@echo "Generated $@"
-
-%.raw.h: %.raw
-	@$(MKDIR_P) $(@D)
-	@echo "namespace alert_tests{" > $@
-	@echo "static unsigned const char $(*F)[] = {" >> $@
-	@$(HEXDUMP) -v -e '8/1 "0x%02x, "' -e '"\n"' $< | $(SED) -e 's/0x  ,//g' >> $@
-	@echo "};};" >> $@
+	@{ \
+	 echo "namespace json_tests{" && \
+	 echo "static unsigned const char $(*F)[] = {" && \
+	 $(HEXDUMP) -v -e '8/1 "0x%02x, "' -e '"\n"' $< | $(SED) -e 's/0x  ,//g' && \
+	 echo "};};"; \
+	} > "$@.new" && mv -f "$@.new" "$@"
 	@echo "Generated $@"