Error message when starting vim: “Failed to set locale category LC_NUMERIC to en_CH” (or en_BR, en_R

mac vim配置后改变系统语言，报出如下警告：

Warning: Failed to set locale category LC_NUMERIC to en_CH.
Warning: Failed to set locale category LC_TIME to en_CH.
Warning: Failed to set locale category LC_COLLATE to en_CH.
Warning: Failed to set locale category LC_MONETARY to en_CH.
Warning: Failed to set locale category LC_MESSAGES to en_CH.

解决办法如下：

First, access your .bash_profile file by typing the following (using vim as text editor):

vim ~/.bash_profile
Inside the file .bash_profile, insert the following line:

export LC_ALL=en_US.UTF-8

source ~/.bash_profile