我跑了brew update，它说 1.8.3.2 可用，所以我安装它并运行brew cleanup以清除旧公式。但是现在当我运行brew doctor它时报告以下错误：
Warning: You have unlinked kegs in your Cellar
Leaving kegs unlinked can lead to build-trouble and cause brews that depend on
those kegs to fail to run properly once built. Run `brew link` on these:
curl
gettext
readline
当我brew link按照建议时，我收到此错误：
Warning: Some keg-only formula are linked into the Cellar.
Linking a keg-only formula, such as gettext, into the cellar with
`brew link <formula>` will cause other formulae to detect them during
the `./configure` step. This may cause problems when compiling those
other formulae.
Binaries provided by keg-only formulae may override system binaries
with other strange results.
You may wish to `brew unlink` these brews:
readline
curl
gettext
我尝试卸载 Git 并使用 1.8.3.1 签出一个分支，但弹出相同的错误，此时我很困惑。
有任何想法吗？