遇到的问题：clang-format 启动自动格式化后，每次自动换行的宽度太窄，导致大量的自动换行，影响代码美观。
解决：
以默认的.clang-format 配置文件为模板，修改ColumnLimit参数：
Language: Cpp
ColumnLimit: 120
最后将.clang-format 文件放到工程的根目录下，重新开启VSC，生效。
其中 Language的设置如下:
Language (LanguageKind)
Language, this format style is targeted at.
Possible values:
LK_None (in configuration: None) Do not use.
LK_Cpp (in configuration: Cpp) Should be used for C, C++.
LK_Java (in configuration: Java) Should be used for Java.
LK_JavaScript (in configuration: JavaScript) Should be used for JavaScript.
LK_ObjC (in configuration: ObjC) Should be used for Objective-C, Objective-C++.
LK_Proto (in configuration: Proto) Should be used for Protocol Buffers (https://developers.google.com/protocol-buffers/).
LK_TableGen (in configuration: TableGen) Should be used for TableGen code.
LK_TextProto (in configuration: TextProto) Should be used for Protocol Buffer messages in text format (https://developers.google.com/protocol-buffers/).
相关的选项含义可以参考这里：http://releases.llvm.org/3.6.0/tools/clang/docs/ClangFormatStyleOptions.html