diff --git a/hermit/Makefile b/hermit/Makefile
index 6c6ca2dfb..0f48aa17a 100644
--- a/hermit/Makefile
+++ b/hermit/Makefile
@@ -41,7 +41,7 @@ RM = rm -rf
 
 CFLAGS_FOR_NEWLIB = -m64 -mtls-direct-seg-refs -mno-red-zone -O3 -march=native -mtune=native -ftree-vectorize $(STACKPROT)
 FFLAGS_FOR_NEWLIB = -m64 -mtls-direct-seg-refs -mno-red-zone -O3 -march=native -mtune=native -ftree-vectorize
-CXXFLAGS_FOR_NEWLIB =
+CXXFLAGS_FOR_NEWLIB = -m64 -mtls-direct-seg-refs -mno-red-zone -O3 -march=native -mtune=native -ftree-vectorize
 LDFLAGS_FOR_NEWLIB =
 NASMFLAGS_FOR_NEWLIB = -felf64
 CFLAGS_FOR_TOOLS = -O2 -Wall
diff --git a/hermit/usr/tests/Makefile b/hermit/usr/tests/Makefile
index 3f1acd196..145c6ed0f 100644
--- a/hermit/usr/tests/Makefile
+++ b/hermit/usr/tests/Makefile
@@ -36,7 +36,7 @@ endif
 
 %.o: %.cpp
 	@echo [CXX] $@
-	$Q$(CXX_FOR_TARGET) -c $(CXXFLAGS_FOR_TARGET) $(CFLAGS_FOR_TARGET) -o $@ $<
+	$Q$(CXX_FOR_TARGET) -c $(CXXFLAGS_FOR_TARGET) -o $@ $<
 
 %.o: %.f90
 	@echo [F90] $@
@@ -52,7 +52,7 @@ all: hello.bin hello++.bin thr_hello.bin jacobi.bin hellof.bin RCCE_minimum.bin
 
 hello++: hello++.o
 	@echo [LD] $@
-	$Q$(CXX_FOR_TARGET) $(LDFLAGS_FOR_TARGET) $(CXXFLAGS_FOR_TARGET) $(CFLAGS_FOR_TARGET) -o $@ $<
+	$Q$(CXX_FOR_TARGET) $(LDFLAGS_FOR_TARGET) $(CXXFLAGS_FOR_TARGET) -o $@ $<
 	$Q$(OBJCOPY_FOR_TARGET) $(KEEP_DEBUG) $@ $@.sym
 	$Q$(OBJCOPY_FOR_TARGET) $(STRIP_DEBUG) $@
 	$Qchmod a-x $@.sym