From c5c58c82a80b28b5b91358a78df0beec4d08d2a0 Mon Sep 17 00:00:00 2001
From: Nico Tonnhofer <wurstnase.reprap@gmail.com>
Date: Sun, 2 Dec 2018 11:55:47 +0100
Subject: [PATCH] Makefile: add an option flag for flto e.g. for make
 regressiontests you could disable it for little faster test simple: make
 regresstiontests USE_FLTO=no

---
 Makefile-ARM | 8 +++++++-
 Makefile-AVR | 8 +++++++-
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/Makefile-ARM b/Makefile-ARM
index 6c472b2..0a5bb4f 100644
--- a/Makefile-ARM
+++ b/Makefile-ARM
@@ -125,6 +125,10 @@ else ifeq ($(MCU), stm32f411)
   STARTUP_FILE = cmsis-startup_stm32f411xe.s
 endif
 
+# Link time optimization is on by default
+ifeq ($(USE_FLTO),)
+  USE_FLTO=yes
+endif
 # Startup definitions. Not target MCU specific.
 CFLAGS  = -D__STARTUP_CLEAR_BSS -D__START=main
 ifeq ($(MCU), lpc1114)
@@ -145,7 +149,9 @@ endif
 CFLAGS += -Wall
 CFLAGS += -Wstrict-prototypes
 CFLAGS += -Os
-CFLAGS += -flto
+ifeq ($(USE_FLTO),yes)
+  CFLAGS += -flto
+endif
 CFLAGS += -ffunction-sections
 CFLAGS += -fdata-sections
 #CFLAGS += -dM -E # To list all predefined macros into the .o file.
diff --git a/Makefile-AVR b/Makefile-AVR
index 216bb79..ed1fede 100644
--- a/Makefile-AVR
+++ b/Makefile-AVR
@@ -113,6 +113,10 @@ TARGET = $(PROGRAM).hex
 # to keep this working and can take a shortcut:
 SOURCES = $(wildcard *.c)
 
+# Link time optimization is on by default
+ifeq ($(USE_FLTO),)
+  USE_FLTO=yes
+endif
 CFLAGS  = $(EXTRA_CFLAGS)
 CFLAGS += -DF_CPU=$(F_CPU)
 CFLAGS += -DMCU_STR=\"$(MCU)\"
@@ -132,7 +136,9 @@ CFLAGS += -Os
 CFLAGS += -ffunction-sections
 CFLAGS += -finline-functions-called-once
 CFLAGS += -mcall-prologues
-CFLAGS += -flto
+ifeq ($(USE_FLTO),yes)
+  CFLAGS += -flto
+endif
 CFLAGS += -Wa,-adhlns=$(@:.o=.al)
 #CFLAGS += -dM -E # To list all predefined macros into the .o file.