Fix windows and two samd builds

Author: tannewt

ports/atmel-samd/Makefile

@@ -270,6 +270,9 @@ SRC_ASF += \
 	hpl/oscctrl/hpl_oscctrl.c \
 	hpl/trng/hpl_trng.c \
 
+# Ignore these errors
+$(BUILD)/asf4/same54/hpl/sercom/hpl_sercom.o: CFLAGS += -Wno-maybe-uninitialized
+
 else ifeq ($(CHIP_FAMILY), same51)
 SRC_ASF += \
 	hal/src/hal_rand_sync.c \

ports/atmel-samd/boards/feather_m4_can/mpconfigboard.mk

@@ -12,3 +12,5 @@ LONGINT_IMPL = MPZ
 
 CIRCUITPY__EVE = 1
 CIRCUITPY_CANIO = 1
+
+CIRCUITPY_LTO = one

ports/atmel-samd/mpconfigport.mk

@@ -124,6 +124,12 @@ ifeq ($(CHIP_FAMILY),same51)
 # No native touchio on SAME51.
 CIRCUITPY_TOUCHIO_USE_NATIVE = 0
 
+ifeq ($(CIRCUITPY_FULL_BUILD),1)
+CIRCUITPY_LTO ?= balanced
+else
+CIRCUITPY_LTO ?= one
+endif
+
 # The ?='s allow overriding in mpconfigboard.mk.
 
 CIRCUITPY_ALARM ?= 1

py/circuitpy_defns.mk

@@ -69,7 +69,7 @@ endif
 
 CIRCUITPY_LTO ?= 0
 ifneq ($(CIRCUITPY_LTO),0)
-CFLAGS += -DCIRCUITPY_LTO=1 -flto=auto -flto-partition=$(CIRCUITPY_LTO)
+CFLAGS += -DCIRCUITPY_LTO=1 -flto=$(shell $(NPROC)) -flto-partition=$(CIRCUITPY_LTO)
 else
 CFLAGS += -DCIRCUITPY_LTO=0
 endif