diff --git a/hermit/Makefile b/hermit/Makefile
index dd770c432..d7fc2fbc7 100644
--- a/hermit/Makefile
+++ b/hermit/Makefile
@@ -51,7 +51,7 @@ STRIP_DEBUG = --strip-debug
 KEEP_DEBUG = --only-keep-debug
 OUTPUT_FORMAT = -O elf32-i386
 
-CFLAGS_FOR_NEWLIB = $(STACKPROT)
+CFLAGS_FOR_NEWLIB = $(STACKPROT) -mtune=native
 LDFLAGS_FOR_NEWLIB =
 NASMFLAGS_FOR_NEWLIB = -felf64
 CFLAGS_FOR_TOOLS = -O2 -Wall
diff --git a/hermit/newlib/Makefile b/hermit/newlib/Makefile
index 2d4f5d532..75f12e32e 100644
--- a/hermit/newlib/Makefile
+++ b/hermit/newlib/Makefile
@@ -17,8 +17,8 @@ ifeq ($V,0)
 endif
 
 default: $(ARCH)
-	$Q$(MAKE) ARCH=$(ARCH) TARGET=$(TARGET) CFLAGS+="-ffreestanding -Wall -I$(NEWLIB)/include -I../../include -I../../arch/$(ARCH)/include" LDFLAGS+="-nostdlib -L$(NEWLIB)/lib" -C examples depend
-	$Q$(MAKE) ARCH=$(ARCH) TARGET=$(TARGET) CFLAGS+="-ffreestanding -Wall -I$(NEWLIB)/include -I../../include -I../../arch/$(ARCH)/include" LDFLAGS+="-nostdlib -L$(NEWLIB)/lib" -C examples
+	$Q$(MAKE) ARCH=$(ARCH) TARGET=$(TARGET) CFLAGS+="-ffreestanding -O3 -Wall -I$(NEWLIB)/include -I../../include -I../../arch/$(ARCH)/include" LDFLAGS+="-nostdlib -L$(NEWLIB)/lib" -C examples depend
+	$Q$(MAKE) ARCH=$(ARCH) TARGET=$(TARGET) CFLAGS+="-ffreestanding -O3 -Wall -I$(NEWLIB)/include -I../../include -I../../arch/$(ARCH)/include" LDFLAGS+="-nostdlib -L$(NEWLIB)/lib" -C examples
 
 $(ARCH):
 	@echo Build newlib