在syntax/c.vim文件末尾中添加如下代码:
"highlight Functions
syn match cFunctions "\<[a-zA-Z_][a-zA-Z_0-9]*\>[^()]*)("me=e-2
syn match cFunctions "\<[a-zA-Z_][a-zA-Z_0-9]*\>\s*("me=e-1
hi cFunctions guifg=#7fd02e cterm=bold ctermfg=yellow
syn match cClass "\<[a-zA-Z_][a-zA-Z_0-9]*\>::"me=e-2
hi cClass guifg=#7fd02e cterm=bold ctermfg=yellow