diff --git a/build/toolchain.arm-gcc.mak b/build/toolchain.arm-gcc.mak
index 5549509f1..9bd156e6e 100644
--- a/build/toolchain.arm-gcc.mak
+++ b/build/toolchain.arm-gcc.mak
@@ -5,11 +5,18 @@ GDB = arm-none-eabi-gdb
 OBJCOPY = arm-none-eabi-objcopy
 SIZE = arm-none-eabi-size
 
+LTO=1
+
 ifeq ($(DEBUG),1)
 SFLAGS += -ggdb3
 else
+ifeq ($(LTO),1)
+SFLAGS += -flto
+else
 SFLAGS += -fdata-sections -ffunction-sections
 LDFLAGS += -Wl,--gc-sections
 endif
+endif
+
 SFLAGS += -mthumb -march=armv7e-m -mfloat-abi=hard -mcpu=cortex-m4 -mfpu=fpv4-sp-d16
 LDFLAGS += $(SFLAGS) -lgcc -Wl,-T,$(LDSCRIPT)