最近，远程登录Ubuntu，编译设备安卓源码出现了错误，如下。
ERROR: vendor/mediatek/proprietary/hardware/interfaces/current.txt differs from expected:
vendor.mediatek.hardware.radio.deprecated@1.1::IOemHook <
vendor.mediatek.hardware.radio.deprecated@1.1::IOemHookIndica <
vendor.mediatek.hardware.radio.deprecated@1.1::IOemHookRespon <
> vendor.mediatek.hardware.radio.deprecated@1.1::IOemHook
> vendor.mediatek.hardware.radio.deprecated@1.1::IOemHookIndica
> vendor.mediatek.hardware.radio.deprecated@1.1::IOemHookRespon
看提交记录，没人改过什么。
上网搜索，也只有一条俄语结果…
错误在下面mk文件中
vendor/mediatek/proprietary/hardware/interfaces/Android.mk
mk文件内容为
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := check-mtk-hidl
LOCAL_MODULE_CLASS := FAKE
my_hal_files := $(shell find $(LOCAL_PATH) -type f -name "*.hal")
intermediates := $(call local-intermediates-dir)
GEN1 := $(intermediates)/current.txt
$(GEN1): $(LOCAL_PATH)/current.txt
@mkdir -p $(dir $@)
@cat $< | cut -d ' ' -f 2 | sort > $@
GEN2 := $(intermediates)/update.txt
$(GEN2): PRIVATE_HAL_FILES := $(sort $(patsubst $(LOCAL_PATH)/%,%,$(my_hal_files)))
$(GEN2): PRIVATE_HAL_PREFIX := vendor/mediatek/hardware/
$(GEN2): $(my_hal_files)
@mkdir -p $(dir $@)
@rm -f $@
@$(foreach f,$(PRIVATE_HAL_FILES), echo $(PRIVATE_HAL_PREFIX)$(f) | sed -e 's/\/\([0-9]\+\.[0-9]\+\)\//@\1::/g' -e 's/\//./g' -e 's/\.hal$$//' >>$@;)
@touch $@
GEN3 := $(intermediates)/diff.txt
LOCAL_ADDITIONAL_DEPENDENCIES += $(GEN3)
$(GEN3): PRIVATE_TXT := $(LOCAL_PATH)/current.txt
$(GEN3): $(GEN1) $(GEN2)
@mkdir -p $(dir $@)
@diff --report-identical-files --ignore-blank-lines --suppress-common-lines --side-by-side $^ > $@ || (echo ERROR: $(PRIVATE_TXT) differs from expected: ; cat $@; false)
@touch $@
include $(BUILD_PHONY_PACKAGE)
include $(call first-makefiles-under,$(LOCAL_PATH))
大致分析一下，是将预先存在的curren.txt内容排序，然后和目录枚举结果排序做比较。如果不一致，就报错。
实际的文件为
out/target/product/module/obj/FAKE/check-mtk-hidl_intermediates/current.txt
out/target/product/module/obj/FAKE/check-mtk-hidl_intermediates/update.txt
查看文件实际内容，实际上是英文"."和"@"排序前后不一致，排序差异导致的问题。
Diff
再看mk文件，发现两个排序方式不一样，第一个排序用的linux命令
@cat $< | cut -d ' ' -f 2 | sort > $@
第二个排序用的Makefile函数
$(GEN2): PRIVATE_HAL_FILES := $(sort $(patsubst $(LOCAL_PATH)/%,%,$(my_hal_files)))
通过网络搜索，sort排序不一致和系统locale有关系
使用locale命令查看ubuntu服务器的设置得到结果，果然有问题
locale: Cannot set LC_CTYPE to default locale: No such file or directory
locale: Cannot set LC_ALL to default locale: No such file or directory
LANG=en_US.UTF-8
LANGUAGE=
LC_CTYPE="en_US.UTF-8"
LC_NUMERIC=zh_CN.UTF-8
LC_TIME=zh_CN.UTF-8
LC_COLLATE="en_US.UTF-8"
LC_MONETARY=zh_CN.UTF-8
LC_MESSAGES="en_US.UTF-8"
LC_PAPER=zh_CN.UTF-8
LC_NAME=zh_CN.UTF-8
LC_ADDRESS=zh_CN.UTF-8
LC_TELEPHONE=zh_CN.UTF-8
LC_MEASUREMENT=zh_CN.UTF-8
LC_IDENTIFICATION=zh_CN.UTF-8
LC_ALL=
再次网络搜索，发现Mac的terminal会设置locale可能导致一些问题..
将terminal的首选项Profiles标签下的Advanced里Set locale environment variables on startup勾选去掉。然后果然好了。
https://askubuntu.com/questions/599808/cannot-set-lc-ctype-to-default-locale-no-such-file-or-directory/778672#778672
