Merge pull request #2031 from jepler/nrf-lto

Enable link-time optimization for nrf targets

ports/nrf/Makefile

@@ -95,8 +95,7 @@ ifeq ($(DEBUG), 1)
   CFLAGS += -fno-inline -fno-ipa-sra
 else
   CFLAGS += -Os -DNDEBUG
-  # TODO: Test with -flto
-  ### CFLAGS += -flto
+  CFLAGS += -flto -flto-partition=none
 endif
 
 

ports/nrf/device/nrf52/startup_nrf52840.c

@@ -116,7 +116,7 @@ void CRYPTOCELL_IRQHandler       (void) __attribute__ ((weak, alias("Default_Han
 void SPIM3_IRQHandler            (void) __attribute__ ((weak, alias("Default_Handler")));
 void PWM3_IRQHandler             (void) __attribute__ ((weak, alias("Default_Handler")));
 
-const func __Vectors[] __attribute__ ((section(".isr_vector"))) = {
+const func __Vectors[] __attribute__ ((used, section(".isr_vector"))) = {
     (func)&_estack,
     Reset_Handler,
     NMI_Handler,