diff --git a/arm11/Makefile b/arm11/Makefile
index b52d531..2ef5cfe 100644
--- a/arm11/Makefile
+++ b/arm11/Makefile
@@ -10,8 +10,8 @@ INCDIRS := source
 INCLUDE := $(foreach dir,$(INCDIRS),-I"$(shell pwd)/$(dir)")
 
 ASFLAGS += $(SUBARCH) $(INCLUDE)
-CFLAGS  += $(SUBARCH) $(INCLUDE) -flto
-LDFLAGS += $(SUBARCH) -Wl,--use-blx,-Map,$(TARGET).map -flto
+CFLAGS  += $(SUBARCH) $(INCLUDE) -flto=auto
+LDFLAGS += $(SUBARCH) -Wl,--use-blx,-Map,$(TARGET).map -flto=auto
 
 include ../Makefile.common
 include ../Makefile.build
diff --git a/arm9/Makefile b/arm9/Makefile
index ae0d9ee..df2eb69 100644
--- a/arm9/Makefile
+++ b/arm9/Makefile
@@ -10,8 +10,8 @@ INCDIRS := source source/common source/filesys source/crypto source/fatfs source
 INCLUDE := $(foreach dir,$(INCDIRS),-I"$(shell pwd)/$(dir)")
 
 ASFLAGS += $(SUBARCH) $(INCLUDE)
-CFLAGS  += $(SUBARCH) $(INCLUDE) -fno-builtin-memcpy -flto
-LDFLAGS += $(SUBARCH) -Wl,--use-blx,-Map,$(TARGET).map -flto
+CFLAGS  += $(SUBARCH) $(INCLUDE) -fno-builtin-memcpy -flto=auto
+LDFLAGS += $(SUBARCH) -Wl,--use-blx,-Map,$(TARGET).map -flto=auto
 LIBS    += -lm
 
 include ../Makefile.common